Ultrastructural and functional aspects of the nucleus infundibularis ventralis in the green frog, Rana esculenta

1973 ◽  
Vol 144 (2) ◽  
pp. 191-217 ◽  
Author(s):  
J. Peute ◽  
J. C. A. Meij
Keyword(s):  
Rana Esculenta ◽  
Green Frog ◽  
Functional Aspects ◽  
Nucleus Infundibularis

Opioids and testicular activity in the frog, Rana esculenta

1993 ◽  
Vol 137 (1) ◽  
pp. 49-NP ◽  
Author(s):  
F. Facchinetti ◽  
A. R. Genazzani ◽  
M. Vallarino ◽  
M. Pestarino ◽  
A. Polzonetti-Magni ◽  
...  
Keyword(s):  
Physiological Activity ◽  
Mammalian Species ◽  
Rana Esculenta ◽  
Cell Degeneration ◽  
Efferent System ◽  
Naltrexone Treatment ◽  
Nucleus Infundibularis ◽  
The Brain

ABSTRACT The presence and activity of brain, pituitary and testicular β-endorphin (β-EP)-like material have been studied in the frog, Rana esculenta, using reverse-phase high-pressure liquid chromatography, coupled with radioimmunoassay and immunocytochemistry. In-vivo and in-vitro treatments with naltrexone were carried out to assess the putative physiological activity of opioid peptides. β(1–31) and (1–27), together with their acetylated forms, have been identified in brain, pituitary and testis. In particular, β-EP(1–31) concentrations peaked during July in the brain and pituitary, whilst in testes maximum concentrations were found in April and November. β-EP immunoreactivity was present in the brain within the nucleus preopticus and nucleus infundibularis ventralis while positive fibres in the retrochiasmatic regions projected to the median eminence. In the testis, interstitial cells, canaliculi of the efferent system, spermatogonia and spermatocytes showed positive immunostaining for β-EP. In intact animals, naltrexone treatment increased plasma and testicular androgen levels and this effect was confirmed in in-vitro incubations of minced testes. Naltrexone also induced a significant increase in germ cell degeneration. Our results indicated that an opioid system modulates the hypothalamus-pituitary-gonadal axis in the frog, Rana esculenta and, for the first time, we have shown that the testicular activity of a non-mammalian species may be regulated by opiates locally. Journal of Endocrinology (1993) 137, 49–57

An androgen receptor in the brain of the green frog Rana esculenta

Life Sciences ◽  
2003 ◽  
Vol 73 (3) ◽  
pp. 265-274 ◽  
Author(s):  
Marina Paolucci
Keyword(s):  
Androgen Receptor ◽  
Rana Esculenta ◽  
Green Frog ◽  
The Brain

Effects of captivity stress on plasma steroid levels in the green frog, rana esculenta, during the annual reproductive cycle

1991 ◽  
Vol 98 (3-4) ◽  
pp. 491-496 ◽  
Author(s):  
Massimo Zerani ◽  
Fabrizia Amabili ◽  
Gilberto Mosconi ◽  
Anna Gobbetti
Keyword(s):  
Reproductive Cycle ◽  
Rana Esculenta ◽  
Green Frog ◽  
Annual Reproductive Cycle

The implication of ribonucleic acids in oviduct growth in the green frog, Rana esculenta

1976 ◽  
Vol 28 (1) ◽  
pp. 96-99
Author(s):  
A. Polzonetti-Magni ◽  
L. Bellini-Cardellini ◽  
V. Boote
Keyword(s):  
Rana Esculenta ◽  
Green Frog ◽  
Ribonucleic Acids

Immunohistochemical localization of chromogranin A and B in the endocrine cells of the alimentary tract of the green frog, Rana esculenta

1994 ◽  
Vol 277 (2) ◽  
pp. 341-349 ◽  
Author(s):  
Loredana D'Este ◽  
Roberto Buffa ◽  
Micaela Pelagi ◽  
Antonio G. Siccardi ◽  
Tindaro Renda
Keyword(s):  
Chromogranin A ◽  
Endocrine Cells ◽  
Alimentary Tract ◽  
Rana Esculenta ◽  
Immunohistochemical Localization ◽  
Green Frog

Relationships between liver testosterone receptor isoforms and aromatase activity in female green frog, Rana esculenta

Life Sciences ◽  
2000 ◽  
Vol 67 (4) ◽  
pp. 373-382 ◽  
Author(s):  
Loredana Assisi ◽  
M.Maddalena Di Fiore ◽  
Claudia Lamanna ◽  
Virgilio Botte
Keyword(s):  
Rana Esculenta ◽  
Aromatase Activity ◽  
Green Frog ◽  
Receptor Isoforms

scholarly journals D-aspartic acid is implicated in the control of testosterone production by the vertebrate gonad. Studies on the female green frog, Rana esculenta

1998 ◽  
Vol 157 (2) ◽  
pp. 199-207 ◽  
Author(s):  
MM Di Fiore ◽  
L Assisi ◽  
V Botte ◽  
A D'Aniello
Keyword(s):  
Amino Acid ◽  
Aspartic Acid ◽  
Rana Esculenta ◽  
Ovarian Follicles ◽  
Sexual Cycle ◽  
Green Frog ◽  
Amphibian Species ◽  
Testosterone Production ◽  
Androgen Synthesis

In the present study we report the occurrence of D-aspartic acid (D-Asp) in the ovary of the green frog Rana esculenta and its putative involvement in testosterone production by the gonad. In the ovary, D-Asp concentrations undergo significant variations during the main phases of the sexual cycle. In spawning females (March), its concentration was low (2.5 +/- 1.1 nmol/g ovary) and during the post-reproductive period (June) it increased and reached its peak level (58.0 +/- 10.1 nmol/g) in October. In that month, vitellogenesis occurs in a new set of ovarian follicles and continues until the next spring. The concentrations of D-Asp in the ovary and of testosterone in the ovary and in the plasma were inversely correlated during the reproductive cycle: when endogenous D-Asp was low (March), testosterone was high (36.9 +/- 4.8 ng/g ovary; 23.1 +/- 2.76 ng/ml plasma) and, in contrast, when the D-Asp concentration was high (October), the testosterone concentration was low (0.86 +/- 0.21 ng/g ovary and 5.0 +/- 1.3 ng/ml plasma). In vivo experiments, consisting of injection of D-Asp (2.0 mumol/g body weight) into the dorsal lymphatic sac of adult female frogs, demonstrated that this amino acid accumulates significantly in the ovary. After 3 h, moreover, it caused a decrease in testosterone level in the plasma of about 80%. This inhibition was reversible: within 18 h after the amino acid injection, as the D-Asp concentration in the ovary decreased, the testosterone titre was restored in both ovary and plasma. In vitro experiments, conducted in isolated ovarian follicles, confirmed this phenomenon and identified these gonadal components as the putative D-Asp targets. Other amino acids (L-Asp, D-Glu, L-Glu, D-Ala and L-Ala) used instead of D-Asp were ineffective. These findings indicate that D-Asp is involved in the control of androgen secretion by the ovary in this amphibian species, revealing a more complex system for control of this androgen synthesis than was previously believed to exist.

Cytological changes in the pars distalis of pituitary of the green frog, Rana esculenta L., during the reproductive cycle

1970 ◽  
Vol 111 (4) ◽  
pp. 505-518 ◽  
Author(s):  
Rakesh K. Rastogi ◽  
G. Chieffi
Keyword(s):  
Reproductive Cycle ◽  
Rana Esculenta ◽  
Green Frog ◽  
Pars Distalis ◽  
Cytological Changes
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