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

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

Apolipoproteins and their electrophoretic pattern throughout the reproductive cycle in the green frog Rana esculenta

1998 ◽  
Vol 119 (4) ◽  
pp. 647-654 ◽  
Author(s):  
Marina Paolucci ◽  
Giulia Guerriero ◽  
Virgilio Botte ◽  
Gaetano Ciarcia
Keyword(s):  
Reproductive Cycle ◽  
Electrophoretic Pattern ◽  
Rana Esculenta ◽  
Green Frog

Argyrophilic Granules in the Pars Distalis of the Green Frog,Rana Esculenta L.II. Effect of Castration and Hormonal Replacement Therapy

1976 ◽  
Vol 43 (1-2) ◽  
pp. 9-13
Author(s):  
Rakesh K. Rastogi ◽  
Prabhat K. Saxena ◽  
G. Chieffi
Keyword(s):  
Replacement Therapy ◽  
Rana Esculenta ◽  
Hormonal Replacement Therapy ◽  
Green Frog ◽  
Pars Distalis ◽  
Hormonal Replacement

Changes in the cytology of the pars distalis of pituitary of green frog, Rana esculenta, under laboratory confinement

1970 ◽  
Vol 15 (3) ◽  
pp. 488-491 ◽  
Author(s):  
Rakesh K. Rastogi ◽  
G. Chieffi
Keyword(s):  
Rana Esculenta ◽  
Green Frog ◽  
Pars Distalis

Effects of Methallibure (ICI 33,828) on the pars distalis of pituitary, testis and thumb pad of the green frog, Rana esculenta L.

1972 ◽  
Vol 123 (3) ◽  
pp. 430-440 ◽  
Author(s):  
R. K. Rastogi ◽  
G. Chieffi ◽  
C. Marmorino
Keyword(s):  
Rana Esculenta ◽  
Green Frog ◽  
Pars Distalis

Argyrophilic Granules in the Pars Distalis of the Green Frog,Rana Esculent A.L. I. Changes During the Reproductive Cycle

1976 ◽  
Vol 43 (1-2) ◽  
pp. 1-8 ◽  
Author(s):  
Prabhat K. Saxena ◽  
Rakesh K. Rastogi ◽  
G. Chieffi
Keyword(s):  
Reproductive Cycle ◽  
Green Frog ◽  
Pars Distalis

scholarly journals Testicular endocrine activity is upregulated by D-aspartic acid in the green frog, Rana esculenta

2004 ◽  
Vol 182 (2) ◽  
pp. 365-376 ◽  
Author(s):  
F Raucci ◽  
L Assisi ◽  
S D'Aniello ◽  
P Spinelli ◽  
V Botte ◽  
...  
Keyword(s):  
Amino Acid ◽  
Aspartic Acid ◽  
Reproductive Cycle ◽  
Rana Esculenta ◽  
Reproductive Period ◽  
Nuclear Antigen ◽  
Green Frog ◽  
Endocrine Activity ◽  
Testosterone Levels ◽  
Stimulation Of

This study investigated the involvement of D-aspartic acid (D-Asp) in testicular steroidogenesis of the green frog Rana esculenta and its effect on stimulation of thumb pad morphology and glandular activity, a typical testosterone-dependent secondary sexual characteristic in this amphibian species. In the testis, D-Asp concentrations vary significantly during the reproductive cycle: they are low in pre- and post-reproductive periods, but reach peak levels in the reproductive period (140-236 nmol/g wet tissue). Moreover, the concentrations of D-Asp in the testis through the sexual cycle positively match the testosterone levels in the gonad and the plasma. The racemase activity evaluated during the cycle expresses its peak when D-Asp and testosterone levels are highest, that is, during the reproductive period, confirming the synthesis of D-Asp from L-Asp by an aspartate racemase. Short-term in vivo experiments consisting of a single injection of D-Asp (2.0 micro mol/g body weight) demonstrated that this amino acid accumulates significantly in the testis, and after 3 h its uptake is coupled with a testosterone increase in both testis and plasma. Moreover, within 18 h of amino acid administration, the D-Asp concentration in the testis decreased along with the testosterone titer to prestimulation levels. Other amino acids (L-Asp, D-Glu and L-Glu) used instead of D-Asp were ineffective, confirming that the significant increase in testicular testosterone was a specific feature of this amino acid. In long-term experiments, D-Asp had been administered chronically to frogs caught during the three phases of the reproductive cycle, inducing testosterone increase and 17beta-estradiol decrease in the gonad during the pre- and post-reproductive period, and vice versa during the reproductive period. The stimulatory effect of D-Asp on testosterone production by the testis is consistent with the stimulation of spermatogenesis and the maturation of thumb pads occurring in D-Asp-treated frogs. In these last animals, there was an increase of seminiferous ampoule area and a higher number of spermatids and sperm. Moreover, in spermatogonia I and II and in spermatocytes, a proliferating cell nuclear antigen (PCNA) intense immunopositivity was observed. In addition, the thumb pads of D-Asp-treated frogs compared with controls showed a significantly thicker epithelial lining, a wider area of their glands with taller secretion cells, and more numerous, PAS-positive-rich secretions. Finally, these results provide functional evidence for a biologic role of D-Asp in amphibian male steroidogenesis; therefore, this unusual amino acid could be considered a modulatory agent for reproductive processes.

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
Sign in / Sign up

Export Citation Format

Share Document