TY - JOUR
T1 - Temperature-dependent prolactin secretion and reproductive biology of the newt Triturus carnifex Laur
AU - Mosconi, Gilberto
AU - Cardinali, Marco
AU - Yamamoto, Kazutoshi
AU - Kikuyama, Sakae
AU - Vellano, Camillo
AU - Polzonetti-Magni, Alberta Maria
PY - 2002
Y1 - 2002
N2 - The effects of temperature on pituitary prolactin (PRL) gene expression and peripheral levels were studied in both male and female newts obtained from wild conditions during reproductive (Experiment I) and nonreproductive (Experiment II) periods; moreover, changes in parameters related to reproductive function are also described. Male and female newts were taken from a pond in February (Experiment I, reproductive period) and maintained for 1 month in tanks at 4 and 18°C. In male newts kept at 4°C, increase of PRL mRNA in the pituitary and plasma PRL was found compared with that measured in those kept at 18°C. The increase in PRL secretion was parallel to that of plasma androgens and related secondary sexual characteristics (SSC) in males and of plasma estradiol-17β and vitellogenin in females. On the contrary, in nonreproductive newts (Experiment II), taken from the field in May, no significant changes in plasma PRL, androgens, and SSC were found in those maintained at low temperature (4°C), whereas low temperature significantly increased PRL mRNA expression in the male pituitary and PRL mRNA plus plasma PRL levels in females. These findings suggest that low temperature regulates PRL secretion in this urodele species, showing a sex- and season-related control mechanism; moreover, low temperature failed to influence the reproductive biology of newts taken from the field in May, after naturally occurring reproduction during winter months.
AB - The effects of temperature on pituitary prolactin (PRL) gene expression and peripheral levels were studied in both male and female newts obtained from wild conditions during reproductive (Experiment I) and nonreproductive (Experiment II) periods; moreover, changes in parameters related to reproductive function are also described. Male and female newts were taken from a pond in February (Experiment I, reproductive period) and maintained for 1 month in tanks at 4 and 18°C. In male newts kept at 4°C, increase of PRL mRNA in the pituitary and plasma PRL was found compared with that measured in those kept at 18°C. The increase in PRL secretion was parallel to that of plasma androgens and related secondary sexual characteristics (SSC) in males and of plasma estradiol-17β and vitellogenin in females. On the contrary, in nonreproductive newts (Experiment II), taken from the field in May, no significant changes in plasma PRL, androgens, and SSC were found in those maintained at low temperature (4°C), whereas low temperature significantly increased PRL mRNA expression in the male pituitary and PRL mRNA plus plasma PRL levels in females. These findings suggest that low temperature regulates PRL secretion in this urodele species, showing a sex- and season-related control mechanism; moreover, low temperature failed to influence the reproductive biology of newts taken from the field in May, after naturally occurring reproduction during winter months.
KW - Newt
KW - Plasma prolactin
KW - Prolactin mRNA expression
KW - Reproductive parameters
KW - Temperature
KW - Triturus carnifex
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U2 - 10.1016/S0016-6480(02)00001-1
DO - 10.1016/S0016-6480(02)00001-1
M3 - Article
C2 - 12093113
AN - SCOPUS:0035988875
SN - 0016-6480
VL - 126
SP - 261
EP - 268
JO - General and Comparative Endocrinology
JF - General and Comparative Endocrinology
IS - 3
ER -