Do the Monoamines in Crab pericardial Organs Play a Role in Peptide Neurosecretion?

1970 ◽  
Vol 53 (3) ◽  
pp. 669-677
Author(s):  
A. BERLIND ◽  
I. M. COOKE ◽  
MARTHA W. GOLDSTONE
Keyword(s):  
Electrical Activity ◽  
Strong Evidence ◽  
Thoracic Ganglion ◽  
Fluorescence Method ◽  
Neurohaemal Organ ◽  
Histochemical Examination ◽  
Pericardial Organ

1. Pericardial organs of Libima emargmata and L. dubia were isolated, the nerves from the thoracic ganglion were stimulated electrically, and propagated electrical activity was recorded. Fluid which bathed the neurohaemal organ was assayed for cardio-excitor effects on the isolated crab heart, when necessary, made tachyphylactic to drugs. 2. Neither 10-6M 5-hydroxytryptamine (5-HT), 10-5M dopamine (DA), nor 10-5M UML applied directly to the pericardial organ evoke release, nor do DA or UML alter release in response to stimulation. 3. The rate of cardio-excitor release is normal in pericardial organs taken from reserpinized animals. Histochemical examination of the pericardial organs by the formaldehyde-induced fluorescence method confirmed depletion of the monoamines. 4. These experiments, taken together, provide strong evidence against a role of monoamines in the release of cardio-excitor hormone from this neurosecretory structure.

Role of intercostal muscles in the rib cage distortions produced by inspiratory loads

1982 ◽  
Vol 52 (3) ◽  
pp. 517-523 ◽  
Author(s):  
M. G. Sampson ◽  
A. De Troyer
Keyword(s):  
Electrical Activity ◽  
Strong Evidence ◽  
Normal Subjects ◽  
The Other ◽  
Reflex Activity ◽  
Quiet Breathing ◽  
Rib Cage ◽  
Intercostal Muscles ◽  
Inspiratory Activity

We studied the patterns of rib cage (RC) deformation in six normal subjects breathing against different resistive and elastic inspiratory loads, and we examined, with concentric needle electrodes, the role played by the inspiratory intercostal muscles in the development of these patterns. Four of the subjects deformed their RC to a more elliptical shape during loaded inspirations; RC anteroposterior diameter became smaller and RC lateral diameter became larger. The RC deformation increased as the load increased, but it appeared to be independent of the nature of the load. Moreover these deformations were associated with a marked increase in the inspiratory activity of the intercostals situated in the lateral parts of the RC and a striking diminution of the activity in the parasternal area. On the other hand, two subjects invariably breathed along their RC relaxation characteristic, and they showed an increased inspiratory activity in all regions of the intercostal musculature. These findings indicate that 1) the pattern of RC deformation during loaded inspirations is closely related to the activity and coordination of the various inspiratory intercostal muscles, and 2) the parasternal intercostals are not necessarily representative of all the inspiratory intercostals. They are also strong evidence against the concept that the parasternal intercostal electrical activity normally recorded during quiet breathing is an excitatory reflex activity.

Concurrent Electrodermal and Eyeblink Conditioning With Masked and Unmasked Stimuli

2021 ◽  
Vol 35 (1) ◽  
pp. 35-42
Author(s):  
José Luis Marcos ◽  
Azahara Marcos
Keyword(s):  
Unconditioned Stimulus ◽  
Strong Evidence ◽  
Eyeblink Conditioning ◽  
Noise Burst ◽  
Conditioning Phase ◽  
Contingency Awareness ◽  
Blank Screen ◽  
Neutral Face ◽  
Fearful Face

Abstract. The aim of this study was to determine if contingency awareness between the conditioned (CS) and unconditioned stimulus (US) is necessary for concurrent electrodermal and eyeblink conditioning to masked stimuli. An angry woman’s face (CS+) and a fearful face (CS−) were presented for 23 milliseconds (ms) and followed by a neutral face as a mask. A 98 dB noise burst (US) was administered 477 ms after CS+ offset to elicit both electrodermal and eyeblink responses. For the unmasking conditioning a 176 ms blank screen was inserted between the CS and the mask. Contingency awareness was assessed using trial-by-trial ratings of US-expectancy in a post-conditioning phase. The results showed acquisition of differential electrodermal and eyeblink conditioning in aware, but not in unaware participants. Acquisition of differential eyeblink conditioning required more trials than electrodermal conditioning. These results provided strong evidence of the causal role of contingency awareness on differential eyeblink and electrodermal conditioning.

The Role of Computer Modeling in Electrocardiography

1990 ◽  
Vol 29 (04) ◽  
pp. 282-288 ◽  
Author(s):  
A. van Oosterom
Keyword(s):  
Electrical Activity ◽  
Computer Modeling ◽  
Body Surface ◽  
Electrical Current ◽  
The Body ◽  
Volume Conductor ◽  
Current Generator ◽  
Cardiac Electrical Activity ◽  
Source Models

AbstractThis paper introduces some levels at which the computer has been incorporated in the research into the basis of electrocardiography. The emphasis lies on the modeling of the heart as an electrical current generator and of the properties of the body as a volume conductor, both playing a major role in the shaping of the electrocardiographic waveforms recorded at the body surface. It is claimed that the Forward-Problem of electrocardiography is no longer a problem. Several source models of cardiac electrical activity are considered, one of which can be directly interpreted in terms of the underlying electrophysiology (the depolarization sequence of the ventricles). The importance of using tailored rather than textbook geometry in inverse procedures is stressed.

BLOCKADE OF THE SURGE OF PROLACTIN AT PRO-OESTRUS BY ADMINISTRATION OF ANTI-OESTROGENIC SUBSTANCE, MER-25

1973 ◽  
Vol 74 (4) ◽  
pp. 769-774 ◽  
Author(s):  
Akira Yokoyama ◽  
Hiroshi Tomogane ◽  
Katuaki Ôta
Keyword(s):  
Strong Evidence ◽  
The Other ◽  
Other Hand

ABSTRACT A non-steroidal oestrogen antagonist, MER-25, was administered to cycling rats for elucidating the role of oestrogen in the surge of prolactin observed on the afternoon of pro-oestrus (POe). In animals injected with 20 mg of MER-25 intramuscularly on the afternoon (16.30 h) of the first day of dioestrus (D-1), the surge of prolactin was blocked while the level of prolactin on the afternoon of POe of these animals was significantly higher than that of the corresponding controls injected with oil. Ovulation was also blocked in these animals treated with the drug on the afternoon of D-l. On the other hand, treatment on the morning (10.30 h) of the 2nd day of dioestrus failed to prevent not only the surge of prolactin but also ovulation. These observations provide strong evidence for the view that oestrogen is responsible for the surge of prolactin on the afternoon of POe, and that the surge is accompanied by that of LH.

scholarly journals Some Regions within Broca's Area Do Respond More Strongly to Sentences than to Linguistically Degraded Stimuli: A Comment on Rogalsky and Hickok ()

2011 ◽  
Vol 23 (10) ◽  
pp. 2632-2635 ◽  
Author(s):  
Evelina Fedorenko ◽  
Nancy Kanwisher
Keyword(s):  
Random Effects ◽  
Language Processing ◽  
Cognitive Neuroscience ◽  
Strong Evidence ◽  
Sentence Comprehension ◽  
Broca’S Area ◽  
Broca's Area ◽  
Review Of The Literature

On the basis of their review of the literature, Rogalsky and Hickok [Rogalsky, C., & Hickok, G. The role of Broca's area in sentence comprehension. Journal of Cognitive Neuroscience, 23, 1664–1680, 2011] conclude that there is currently no strong evidence for the existence of “sentence-specific processing regions within Broca's area” (p. 1664). Their argument is based, in part, on the observation that many previous studies have failed to detect an effect in the left inferior frontal regions for contrasts between sentences and linguistically degraded control conditions (e.g., lists of unconnected words, lists of nonwords, or acoustically degraded sentence stimuli). Our data largely replicate this lack of activation in inferior frontal regions when traditional random-effects group analyses are conducted but crucially show robust activations in the same data for the same contrasts in almost every subject individually. Thus, it is the use of group analyses in studies of language processing, not the idea that sentences robustly activate frontal regions, that needs to be reconsidered. This reconsideration has important methodological and theoretical implications.

MELANIN PIGMENTATION IN BOVINE PINEAL GLAND AND ITS POSSIBLE CORRELATION WITH GONADAL FUNCTION

1958 ◽  
Vol 36 (2) ◽  
pp. 227-235 ◽  
Author(s):  
Enrique Santamarina
Keyword(s):  
Pineal Gland ◽  
Strong Evidence ◽  
Spectrophotometric Analysis ◽  
Black Pigment ◽  
Gonadal Function ◽  
Melanin Pigmentation ◽  
Degenerative Process ◽  
Aging Phenomenon ◽  
Bovine Pineal Gland

The incidence of melanin in the bovine pineal gland was studied in 880 glands. Spectrophotometric analysis and chemical and cytochemical methods identified the black pigment present in the bovine pineal gland as melanin. No melanin was found in bulls 4 and 5 years of age nor in heifers of about 18 months. In pregnant cows over 5 years of age melanin was found in 5.4% of the pineal glands. Non-pregnant cows of the same age exhibited melanin in 8.5% of the pineal glands. Castrated male cattle between 18 and 24 months of age showed 49.6% of the pineal glands with macroscopical signs of melanization. As much as 67% of the pineal glands of steers from some herds contained melanin. In intact cattle melanin in the pineal appears to be mainly an aging phenomenon. The fact that castration in male cattle causes hypertrophy of the pineal gland followed by a degenerative process in which melanin is involved seems to give strong evidence of a pineal gonadal interrelationship. The possible role of the hormones in the phenomenon of melanin formation is discussed.

scholarly journals A dynamic, imperturbable link between midbrain activity and saccade velocity

2020 ◽  
Vol 123 (2) ◽  
pp. 451-453
Author(s):  
Joshua A. Seideman
Keyword(s):  
Eye Movement ◽  
Strong Evidence ◽  
Neural Control ◽  
Oculomotor Control ◽  
Saccadic Eye Movement ◽  
Saccade Velocity ◽  
Midbrain Structure ◽  
Instantaneous Control ◽  
Dynamic Moment

We make a saccadic eye movement once every few hundred milliseconds; however, the neural control of saccade execution is not fully understood. Dynamic, moment-by-moment variations in saccade velocity are typically thought to be controlled by neurons in the lower, but not the upper regions of the brainstem. In a recent report, Smalianchuk et al. (Smalianchuk I, Jagadisan UK, Gandhi NJ. J Neurosci 38: 10156–10167, 2018) provided strong evidence for a role of the superior colliculus, a midbrain structure, in the instantaneous control of saccade velocity, suggesting the revision of long-standing models of oculomotor control.

Pelvic aspiration in the American alligator (Alligator mississippiensis)

2000 ◽  
Vol 203 (11) ◽  
pp. 1679-1687 ◽  
Author(s):  
C.G. Farmer ◽  
D.R. Carrier
Keyword(s):  
Electrical Activity ◽  
Lung Ventilation ◽  
Rectus Abdominis ◽  
Transversus Abdominis ◽  
Alligator Mississippiensis ◽  
Abdominal Pressure ◽  
American Alligator ◽  
Diaphragmatic Breathing ◽  
Pelvic Muscles

The pelvis of crocodilians is highly derived in that the pubic bones are isolated from the acetabulum and are attached to the ischia via moveable joints. We examined the possible role of this unusual morphology in lung ventilation by measuring ventilation, abdominal pressure and the electrical activity of several abdominal and pelvic muscles in the American alligator (Alligator mississippiensis). We found that the activity of two pelvic muscles, the ischiopubis and ischiotruncus muscles, was correlated with inspiration; these muscles rotate the pubes ventrally and thereby increase abdominal volume. During expiration, contraction of the rectus abdominis and transversus abdominis rotates the pubes dorsally. We suggest that this mechanism facilitates diaphragmatic breathing by creating space for caudal displacement of the viscera during inspiration. Because birds also use a dorso-ventral movement of the pelvis to effect ventilation, some form of pelvic aspiration may be plesiomorphic for archosaurs.

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