Male reproductive tract, spermatophores and spermatophoric reaction in the giant octopus of the North Pacific, Octopus dofleini martini

The male reproductive tract of Octopus dofleini martini lies enclosed in the genital bag, inside the mantle cavity. It consists of the testis, vas deferens proximale, spermatophoric gland system I (seminal vesicle), spermatophoric gland system II (prostate), vas deferens distale, spermatophoric sac (Needham’s sac) and the terminal spermatophoric duct. The spermatozoa, which upon leaving the testis are as yet not encased, pass first into the vas deferens proximale, which in its gross appearance resembles the epididymis; they then traverse the two tubular spermatophoric gland systems I and II, where they become encased into the spermatophores. Subsequently the spermatophores pass through the vas deferens distale into the spindle-shaped spermatophoric sac, and from there they enter singly the terminal spermatophoric duct consisting of the diverticulum and terminal organ or ‘penis’. The slender cylindrical body of the spermatophore is about 1 m long and consists of two parts, approximately equal in length. The thicker ‘proximal’ ‘male-oriented’ portion, which emerges first from the orifice of the ‘penis’, contains the tightly coiled sperm rope suspended in a viscous and transparent fluid, the spermatophoric plasma; the thinner ‘distal’ ‘femaleoriented’ half of the spermatophore is taken up by the rod-shaped, hyaline core of the ejaculatory apparatus. In between is located the cement body, and the amber-coloured cement liquid. At the distal end of the spermatophore the outer coating forms a cap and a filamentous appendage, the cap-thread. Chemical analyses were performed on spermatozoa, spermatophoric plasma, cement liquid, outer tunic and the hyaline core of the ejaculatory apparatus, obtained from freshly recovered spermatophores. Glycogen was identified as a major constituent of spermatozoa. The extraordinarily high dry-weight content of spermatophoric plasma (nearly 30%) was shown to be largely due to bound amino sugar, carbohydrate, peptide and protein. A peptide separated from the spermatophoric plasma by ultrafiltration was found to be made up to a great extent of aspartic acid and serine. The outer tunic, a tough and elastic membrane, which envelops the body of the spermatophore, was shown to consist mostly of a protein which is rich in proline, lysine, aspartic acid and threonine. The mechanics of the spermatophoric reaction in vitro have been studied in spermatophores extracted manually from the male octopus and placed in sea-water. The complete spermatophoric reaction under such conditions lasted 1 to 2 h. During that interval the sperm rope gradually advanced a distance of about 1 m, from the proximal towards the distal end of the spermatophore. The terminal phase of this process involved an evagination of the ejaculatory apparatus, followed by a rapid movement of the sperm rope; as the sperm rope entered the end portion of the spermatophore, the latter ballooned out into an egg-shaped bladder. Among the factors which contribute to the formation of the spermatophoric bladder, the most important ones are (i) the elasticity of the membranes of the spermatophore, (ii) the extrusion, and subsequently evagination, of the ejaculatory apparatus, and (iii) the influx of sea-water into the spermatophore’s body which causes an approximately fivefold increase in the volume of spermatophoric plasma. Concomitantly with the uptake of sea-water, the dry weight of the spermatophorie plasma declines but the sodium chloride concentration increases. However, the osmolality of the spermatophoric plasma, as assessed by freezingpomt depression, is not altered during the spermatophoric reaction. Events at copulation, that is under conditions in vivo , closely resembled those observed in spermatophores undergoing a spermatophoric reaction in vitro . An interval of 2 to 3 h usually elapsed from the time when the male, using his hectocotylized arm, mserted mto the female the distal (female-oriented) end of a spermatophore, to the moment of the male's withdrawal. After accomplished copulation two spermatophores were usually found firmly lodged in the two oviducts. The sperm-free remnants of the spermatophore bodies dangled free from the orifices of the oviducts. Upon dissection of recently mated females the spermatophoric bladder was usually found within the oviduct, held firmly in position by the evaginated ejaculatory apparatus.

2021 ◽  
Vol 8 ◽  
Author(s):  
Eduardo G. Aisen ◽  
Wilfredo Huanca López ◽  
Manuel G. Pérez Durand ◽  
Edita Torres Mamani ◽  
Juan C. Villanueva Mori ◽  
...  

The viscous seminal plasma (SP) is currently a major impediment to the handling of ejaculate and the development of some biotechnologies in South American camelids. The vas deferens-collected spermatozoa of alpacas is a useful technique to avoid this problem. On the other hand, SP contains a large protein component that has been implicated in the function of spermatozoa within the female reproductive tract. In this sense, the low fertility achieved using transcervical insemination with frozen-thawed spermatozoa in alpacas could be improved by adding SP. This study aimed to evaluate the effect of the whole SP on some in vitro parameters of alpaca spermatozoa after the freezing-thawing-process and the fertility after artificial insemination. It would contribute to a better understanding of the interaction between thawed sperm cells and SP. Spermatozoa were obtained by surgically diverted vas deferens. The samples were diluted with a Tris-based extender, packaged in straws, and frozen. At thawing, each straw was divided into two post-thawing conditions: with the addition of 10% of PBS (control) or with 10% SP (treatment). The sperm cells were evaluated using dynamic parameters, sperm cell morphology, and morphometry. Fertility was assessed by an artificial insemination trial. All in vitro parameters were analyzed by ANOVA. A heterogeneity test was scheduled for the fertility trial. After the freezing-thawing process, motility and plasma membrane functionality was improved when SP was added. No differences were found for post-thaw viability between the control and treatment samples. The percentage of normal cells was higher with SP at post-thawing, and a decrease of the presence of bent tailed spermatozoa with a droplet in the SP group was observed. The length of the head spermatozoa was 3.4% higher in the samples with PBS compared to those in which SP was added. Females pregnant at day 25 post-insemination were 0/12 (with SP inside the straw) and 1/10 (without SP inside the straw). In conclusion, the presence of 10% SP at post-thawing improves sperm cells' motility, functionality, and morphology, indicating that it would be beneficial to improve the frozen-thawed alpaca's physiology spermatozoa. More fertility trials must be developed to increase this knowledge.


Parasitology ◽  
1966 ◽  
Vol 56 (2) ◽  
pp. 347-358 ◽  
Author(s):  
A. O. Anya

The histological anatomy of the male reproductive tract as well as the cytochemistry of the cells of different regions of the male tract in Aspiculuris tetraptera are described.It is shown that there are at least three different regions of the vas deferens, each of which releases one or more substances into the lumen of the male system and thus contributes to the composition of the semen. The histochemical nature of these secretions is given and it is suggested that the secretions of the distal vas deferens are oxytocic.My thanks are due to Professor J. D. Smyth of the Australian National University, Canberra, for the gift of RNA-ase (L. Light and Co.) and some other histochemical reagents, to Dr T. R. R. Mann, C.B.E., F.R.S., and Dr D. L. Lee, for helpful discussions during the course of this study and for reading the draft manuscript.


2004 ◽  
Vol 16 (5) ◽  
pp. 561 ◽  
Author(s):  
P. N. Schlegel

Azoospermia may occur because of reproductive tract obstruction (obstructive azoospermia) or inadequate production of spermatozoa, such that spermatozoa do not appear in the ejaculate (non-obstructive azoospermia). Azoospermia is diagnosed based on the absence of spermatozoa after centrifugation of complete semen specimens using microscopic analysis. History and physical examination and hormonal analysis (FSH, testosterone) are undertaken to define the cause of azoospermia. Together, these factors provide a >90% prediction of the type of azoospermia (obstructive v. non-obstructive). Full definition of the type of azoospermia is provided based on diagnostic testicular biopsy. Obstructive azoospermia may be congenital (congenital absence of the vas deferens, idiopathic epididymal obstruction) or acquired (from infections, vasectomy, or other iatrogenic injuries to the male reproductive tract). Couples in whom the man has congenital reproductive tract obstruction should have cystic fibrosis (CF) gene mutation analysis for the female partner because of the high risk of the male being a CF carrier. Patients with acquired obstruction of the male reproductive tract may be treated using microsurgical reconstruction or transurethral resection of the ejaculatory ducts, depending on the level of obstruction. Alternatively, sperm retrieval with assisted reproduction may be used to effect pregnancies, with success rates of 25–65% reported by different centres. Non-obstructive azoospermia may be treated by defining the cause of low sperm production and initiating treatment. Genetic evaluation with Y-chromosome microdeletion analysis and karyotype testing provides prognostic information in these men. For men who have had any factors potentially affecting sperm production treated and remain azoospermic, sperm retrieval from the testis may be effective in 30–70% of cases. Once sperm are found, pregnancy rates of 20–50% may be obtained at different centres with in vitro fertilisation and intracytoplasmic sperm injection.


2019 ◽  
Author(s):  
Jing Gao ◽  
Guanqun Gao ◽  
Lulu Dai ◽  
Jiaxing Wang ◽  
Hui Chen

Abstract Background Trypophloeus Klimeschi Eggers (Coleoptera: Curculionidae: Scolytinae) is one of the most destructive pests of Populus alba var. pyramidalis (Bunge), resulting in significant losses in economic, ecological and social benefits in China’s northwest shelter forest. But research of reproductive system, spermiogenesis and spermatozoon ultrastructure of T. klimeschi that is basis of phylogeny, reproductive biology and controlling is still black. Results The male reproductive organ of T. klimeschi is composed of testis, seminal vesicle, strand shaped accessory gland containing long branch of strand shaped accessory gland and short branch of strand shaped accessory gland, curly accessory gland, vas deferens and a common ejaculatory duct. The number of sperm per cyst is 350~512. Its spermatozoon is slender, measuring about 75 μm in length and 0.5 μm in wide and composed of a 3-layred acrosomal complex, a nucleus with two different states of aggregation, two mitochondrial derivatives with dark crystal, a 9+9+2 axoneme that run more or less parallel to mitochondrial derivatives, two crystalline accessory bodies with a big compact “puff”-like expansion. Especially in the seminal vesicle, its long flagella folded into several turns and the whole sperm is wrapped in a film.Conclusion The general morphology of male reproductive tract, the spermatogenesis and the spermatozoa of T. klimeschi are, for the most part, similar to the majority of the Curculionidae. However, some distinct differences were found: the low electron-dense band in the cytoplasm of spermatocytes; two different aggregation states of spermatozoon nucleus; especially the stored way of T. klimeschi spermatozoa.


2012 ◽  
Vol 67 (11-12) ◽  
pp. 571-579 ◽  
Author(s):  
El-Sayeda A. El-Kashoury ◽  
Hesham I. El-Askary ◽  
Zeinab A. Kandil ◽  
Mohamed A. Salem ◽  
Amany A. Sleem

Hydrodistilled oils of the fresh aerial parts of Mentha suaveolens Ehrh. cultivated in Egypt were prepared from samples collected along the four seasons. The percentage yields of these essential oils were 0.50%, 0.52%, 0.60%, and 0.47% of the dry weight for winter, spring, summer, and autumn samples. GC/MS analyses of all samples revealed a qualitative and quantitative variability in the oil composition. The total number of compounds identified was 46 among which 15 were common in all samples. The oxygenated compounds constituted about 45%, 46%, 63%, and 44% of the total composition of the oils for winter, spring, summer, and autumn samples, respectively. Carvone was the major constituent in spring, summer, and autumn samples (about 31%, 56%, and 35%, respectively), while limonene (ca. 26%) was the major constituent of the winter sample followed by carvone (ca. 25%). The essential oil of the highest yield (full-fl owering summer sample), with the highest oxygenated constituents and carvone contents, was screened for certain biological activities. It exhibited analgesic and acute anti-inflammatory activities (75% and 82% relative to indomethacin). It also showed a potent in vivo antioxidant activity (96% relative to vitamin E). In addition, it exerted moderate cytotoxic, hepatoprotective, and in vitro antioxidant activities. Moreover, the oil had a potent antifungal activity against Candida albicans (MIC = 4 μg/ml), Saccharomyces cerevisiae (MIC = 5.2 μg/ml), and Aspergillus niger (MIC = 6.8 μg/ml).


1994 ◽  
Vol 68 (3) ◽  
pp. 255-258
Author(s):  
P.N. Sharma ◽  
G. Swarnakar ◽  
R.E.B. Hanna

AbstractThe ultrastructure of various regions of the male reproductive tract and the prostate gland of Cotylophoron cotylophorum (Trematoda: Digenea) is described. The internal lining of the entire male duct system is syncytial in nature, and regional variation is quite evident. The syncytial epithelium of the vas deferens and seminal vesicle is very thin, flat and lamellate and the lumen is packed with spermatozoa. In the pars musculosa (PM) the syncytium is also flat but lamellae are sparsely distributed and anastomosed at places to form loops. The syncytium of the PM is invested by several layers of circular and longitudinal muscle. The pars prostatica (PP) is lined by an uneven but moderately thick syncytial epithelium with nuclei projecting into the lumen. The syncytium bears numerous very long lamellae. The ejaculatory duct epithelium is devoid of lamellae. It is even and moderately thick throughout. The prostate gland cells are uneven in outline and bear long ducts which open into the lumen of the PP. They show an ultrastructural organization suggestive of protein secretion.


2020 ◽  
Author(s):  
Ye YuXuan ◽  
Tu YiSheng ◽  
Yu Xiao ◽  
Huang Qian ◽  
Yuan Huihui

Abstract Background:the secondary metabolite of H. serrata, huperzine A (HupA) can be used in the treatment of Alzheimer’s disease and can improve the cognitive function of patients. The use of in vitro culture and secondary metabolism engineering to obtain secondary metabolites is the most effective method to solve a lack of HupA sources and protect H. serrata as a natural resource. This study was based on the in vitro thallus culture conditions for H. serrate, and different concentrations of alkaloid precursor amino acids (lysine, aspartic acid, and trytophan) were added. We found that addition of different amino acids to thallus cultures had different effects on HupA accumulation. Transcriptome sequencing was carried out on thalli with significant differences in the HupA content due to treatment with different amino acids for differential analysis, and real-time fluorescence quantitative PCR was used for validation to examine the functional genes involved in exogenous amino acid regulation of HupA accumulation in thalli.Results:We found that addition of 1 mmol·L−1 aspartic acid (D) solution promoted HupA accumulation, at a level of 84.05 μg·g−1 dry weight (DW), which was 1.29-fold that of the control (CK: 65.15 μg·g−1 DW). Addition of 4 mmol·L−1 lysine (K) solution significantly inhibited HupA accumulation, at a level of 48.42 μg·g−1 DW, which was 0.75-fold that of the control.Transcriptome sequencing-bioinformatics alignment analysis of the aforementioned materials showed that in GO alignment analysis, functions were annotated for 16,258 unigenes. From the statistical analysis of the DEGs of the three groups, we found that there were 1046, 782, and 1586 DEGs for CK vs D, CK vs K, and D vs K, respectively, with D vs K having the most DEGs. DEGs that were enriched in KEGG metabolic pathways and validated by fluorescence quantitative PCR included PANK1, GDH2, APX, HA1, ND4L, and COX1. Conclusions:The above results showed that HupA content differences in D and K treatments were directly proportional to DEGs. Gene expression differences are the molecular basis that affects HupA accumulation in in vitro thallus cultures. PANK1 and GDH2 encode enzymes that synthesize an alkaloid intermediate.


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