Morphology of the neuroendocrine systems of two larval blackflies, Prosimulium mixtum/fuscum and Simulium venustum

1976 ◽  
Vol 54 (9) ◽  
pp. 1579-1584 ◽  
Author(s):  
William J. Condon ◽  
Roger Gordon ◽  
Charles H. Bailey

The anatomical relations of the neuroendocrine systems of simuliid larvae Prosimulium mixtum/fuscum and Simulium venustum were examined histologically. The neuroendocrine system in the brain showed morphological similarities to culicids (viz., three pairs of cerebral neurosecretory cell clusters, one pair of nervi corporis cardiaci entering the corpus cardiacum glandular system). The retrocerebral glandular portion of the neuroendocrine system was comprised of a corpus allatum, corpora cardiaca, and surrounding peritracheal gland. The morphology of the blackfly neuroendocrine system is discussed in relation to those of other families of Nematocera and higher Diptera.

1972 ◽  
Vol 57 (3) ◽  
pp. 755-763
Author(s):  
E. A. BERNAYS ◽  
R. F. CHAPMAN

1. The electrical resistance across the tips of the maxillary palps is not affected by stimulation of the palps, but increases to the normal level found after feeding as a result of distension of the foregut with agar or injection of corpus cardiacum homogenates into the haemolymph. 2. No increase in resistance occurs if the posterior pharyngeal nerves or the frontal connectives are cut. 3. It is inferred that distension of the foregut stimulates stretch receptors which, acting via the posterior pharyngeal nerves, the frontal connectives and the brain, cause the release of hormone from the storage lobes of the corpora cardiaca. This hormone acts on the terminal sensilla of the palps, causing them to close and so increasing the resistance across the palps. 4. Release of the diuretic hormone is controlled via the same pathway.


2010 ◽  
Vol 10 (156) ◽  
pp. 1-19 ◽  
Author(s):  
Pawel Marciniak ◽  
Neil Audsley ◽  
Mariola Kuczer ◽  
Grzegorz Rosinski

1973 ◽  
Vol 105 (5) ◽  
pp. 725-731 ◽  
Author(s):  
C. F. Hinks

AbstractLarvae and eonymphs of the diprionid sawflies Neodiprion lecontei (Fitch), Neodiprion swainei Midd., and Diprion hercyniae (Htg.) were dissected and stained to demonstrate the nervous system and endocrine organs. Morphologically and anatomically the endocrine organs in both larvae and eonymphs of all three species are very similar. The cephalic structures comprise lateral and medial neurosecretory cells in the brain which discharge their secretions through a single pair of nerves (NCC) to the corpora cardiaca. The NCC divide before they enter the corpora cardiaca sending a branch to the corresponding corpus allatum. No other nervous connections with these organs are apparent.Paired neurohaemal organs occur in each thoracic segment, forming distinct dilations on slender nerves arising from the ventral cord connectives. They receive secretions from groups of lateral neurosecretory cells in the thoracic ganglia.Each abdominal ganglion has three neurohaemal organs associated with it, a single small spherical structure antero-medially, and paired lateral organs of a diffuse structure, overlying the base of each segmental nerve. They are less conspicuous than the thoracic organs and have different staining properties.


1976 ◽  
Vol 65 (3) ◽  
pp. 565-575
Author(s):  
S. W. Nicolson

The diuresis which follows the pupal-adult ecdysis of Pieris brassicae is hormonally controlled. Use of the isolated Malpighian tubules as a bioassay shows the presence of substantial diuretic activity in homogenates of the brain and corpus cardiacum-corpus allatum complex. The hormone is probably produced in the brain and released from a storage site in the corpora cardiaca. The tubules of the butterfly are maximally responsive to the diuretic hormone at the time of eclosion.


1975 ◽  
Vol 63 (1) ◽  
pp. 143-159
Author(s):  
J. E. Treherne ◽  
P. G. Willmer

An accelerated water-loss was observed in decapitated individuals, no equivalent increase being obtained following severance of the nervous connectives in the neck. Injection of brain and, to a lesser extent, corpus cardiacum extract resulted in a significant reduction in the rate of loss of water from decapitated individuals. The accelerated water-loss observed following decapitation appeared not to result from significant increase in excretory output or loss of water through the spiracles. It is suggested that integumentary transpiration may be affected by a blood-borne factor, or factors, which originate in the brain and corpus cardiacum.


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