Journal ArticleDOI
Suppression of annual testicular development in Indian Palm Squirrel, Funambulus pennanti by 8 hr temporal relationship of serotonin and dopamine precursor drugs
TLDR
Results indicate that induced suppression of gonadal function in a fashion similar to seasonal regression leading to non-breeding condition is the consequence of specific phase relationship (8 hr) between serotonergic and dopaminergic activities and not due to Serotonin or dopamine alone.Abstract:
Daily injections of 5-HTP (5-hydroxytryptophan, serotonin precursor) and L-DOPA (L-Dihydroxyphenylalanine, dopamine precursor) given 8 hour apart inhibited normal testicular growth in seasonally breeding Indian Palm Squirrel,Funambuluspennanti leading to complete gonadal atrophy, which was maintained till the end of the study. HCG administration induced higher degree of gonadal development but, when the two treatments (HCG + 8 hr relationship of 5-HTP and L-DOPA) were given simultaneously no significant difference was observed compared to control.read more
Citations
More filters
Journal ArticleDOI
Temporal phase relation of circadian neural oscillations alters RFamide-related peptide-3 and testicular function in the mouse.
TL;DR: Findings not only suggest the modulation of gonadal development in mice by changing the temporal phase relation of serotonergic and dopaminergic oscillations, but also demonstrate an inverse correlation of RFRP-3 neurons and gonadal activity in both control and experimental conditions.
Journal ArticleDOI
Temporal synergism of neurotransmitters (serotonin and dopamine) affects testicular development in mice.
TL;DR: It is concluded that normal somatic and gonadal growth of pre-puberal mice may be suppressed with an 8-hr phase relation of circadian serotonergic and dopaminergic oscillations, which accelerated the rate of gonadal maturation and led to more or less similar gonadal development as in the control mice.
Journal ArticleDOI
Reproductive phase dependent circadian variation in hypothalamic concentration of serotonin, dopamine and peripheral thyroxine levels in Japanese Quail following 5-HTP and L-DOPA administration at specific time intervals
TL;DR: The findings suggest that the temporal phase relation of circadian serotonergic and dopaminergic oscillator varies as a function of reproductive status of the bird, and breeding/non-breeding conditions may be induced experimentally by changing the phase relationof these oscillations.
Journal ArticleDOI
Effects of simulated hypo- and hyper-reproductive conditions on the characteristics of circadian rhythm in hypothalamic concentration of serotonin and dopamine and in plasma levels of thyroxine, triiodothyronine, and testosterone in Japanese quail, Coturnix coturnix japonica.
Pankaj Kumar,Atanu Kumar Pati,Jag Mohan,K.V.H. Sastry,Jagbir Singh Tyagi,Chandra Mohini Chaturvedi +5 more
TL;DR: It is suggested that administration of 5‐HTP and L‐DOPA at specific time interval and variation in pineal functions that modulate reproductive responses also alter the circadian pattern (acrophase and amplitude) of hypothalamic serotonin and dopamine, maintaining a specific phase relation between these cycles and breeding status.
Journal ArticleDOI
Influence of temporal relationships between serotonergic and dopaminergic precursors on the regulation of gonadal development in birds.
TL;DR: Results are in agreement with the internal coincidence model of photoperiodic time measurement and indicate that birds can detect specific phase relationship between the two neural oscillations for their reproductive regulations and circadian organization is intricately involved in the regulation of seasonality.
References
More filters
Journal ArticleDOI
Temporal synergism of corticosterone and prolactin controlling gonadal growth in sparrows.
TL;DR: The seasonal cycle of reproductive photorefractoriness and photosensitivity is controlled by a changing relation between the daily rhythms of plasma concentrations of corticosterone and prolactin.
Journal ArticleDOI
Decarboxylation of exogenous L-5-hydroxytryptophan after destruction of the cerebral raphe system.
TL;DR: The results indicate that the formation of 5‐HT in the cerebral cortex from exogenous l‐5‐HTP, after inhibition of the peripheral aromatic amino acid decarboxylase, occurs predominantly in 5-HT containing nerve endings possibly by a specific 5‐ HTP‐decarboxyating enzyme.
Journal ArticleDOI
Resetting the annual cycle with timed daily injections of 5-hydroxytryptophan and L-dihydroxyphenylalanine in Syrian hamsters.
John M. Wilson,Albert H. Meier +1 more
TL;DR: The results indicate that the endogenous mechanism controlling seasonality (scotosensitivity and scotorefractoriness) in the Syrian hamster may be reset by drugs that influence serotonergic and catecholaminergic activity.
Journal ArticleDOI
Temporal Variations in Gonadal and Body Fat Responses to Daily Injections of 5-Hydroxytryptophan (5-HTP) and Dihydroxyphenylalanine (DOPA) in the Gulf Killifish, Fundulus grandis
TL;DR: The drug effects persist for at least 3 weeks following drug treatment indicating a possible resetting of an endogenous mechanism involved in seasonality.
Journal ArticleDOI
Circadian neurotransmitter activity resets the endogenous annual cycle in a migratory sparrow
Larry J. Miller,Albert H. Meier +1 more
TL;DR: Daily injections of neurotransmitter‐affecting drugs induced spring migratory and reproductive conditions in white‐throated sparrows, Zonotrichia albicollis, during the fall and changes in the temporal relations of circadian neural activities may account for seasonal alterations of metabolism and behavior.
Related Papers (5)
The effect of different temporal relationships of 5‐hydroxytryptophan (5‐HTP) and l‐dihydroxyphenylalanine (L‐DOPA) on reproductive and metabolic responses of migratory red‐headed bunting (Emberiza bruniceps)
Timed daily injections of neurotransmitter precursors alter the gonad and body weights of spotted munia, Lonchura punctulata, maintained under short daily photoperiods
C. M. Chaturvedi,S. K. Prasad +1 more