scholarly journals Effect of age, injury, and predator odors or settlement and shelter selection by lobster Homarus amencanus postlarvae

1993 ◽  
Vol 93 ◽  
pp. 119-129 ◽  
Author(s):  
B Boudreau ◽  
E Bourget ◽  
Y Simard
Keyword(s):  
Predator Odors ◽  
Shelter Selection ◽  
Effect Of Age

Effect of Age in Methylphenidate-Induced Taste Avoidance and Related BDNF/Trkb in the Insular Cortex

2014 ◽  
Author(s):  
Bradley Wetzell ◽  
Mirabella M. Muller ◽  
Jennifer L. Cobuzzi ◽  
Zachary E. Hurwitz ◽  
Kathleen Decicco-Skinner ◽  
...  
Keyword(s):  
Insular Cortex ◽  
Taste Avoidance ◽  
Effect Of Age

Effect of age and prior knowledge on associative and item memory for brands

2012 ◽  
Author(s):  
Praggyan Mohanty ◽  
S. Ratneshwar ◽  
Moshe Naveh-Benjamin
Keyword(s):  
Prior Knowledge ◽  
Item Memory ◽  
Effect Of Age

The effect of age on blink reflex excitability recovery

2011 ◽  
Vol 42 (01) ◽  
Author(s):  
M. Kofler ◽  
H. Kumru ◽  
J. Schaller
Keyword(s):  
Blink Reflex ◽  
Reflex Excitability ◽  
Effect Of Age

Effects of ageing and exogenous melatonin on pituitary responsiveness to GnRH in rats

Reproduction ◽  
2000 ◽  
pp. 151-156 ◽  
Author(s):  
E Diaz ◽  
D Pazo ◽  
AI Esquifino ◽  
B Diaz
Keyword(s):  
Body Weight ◽  
Reproductive System ◽  
Plasma Concentrations ◽  
Pituitary Hormones ◽  
Female Rats ◽  
Control Groups ◽  
Melatonin Treatment ◽  
Exogenous Melatonin ◽  
Reproductive Axis ◽  
Effect Of Age

The effect of age and melatonin on the activity of the neuroendocrine reproductive system was studied in young cyclic (3-5 months-old), and old acyclic (23-25 month-old) female rats. Pituitary responsiveness to a bolus of GnRH (50 ng per 100 g body weight) was assessed at both reproductive stages in control and melatonin-treated (150 micrograms melatonin per 100 g body weight each day for 1 month) groups. After this experiment, female rats were treated for another month to study the influence of ageing and melatonin on the reproductive axis. Plasma LH, FSH, prolactin, oestradiol and progesterone were measured. A positive LH response to GnRH was observed in both control groups (cyclic and acyclic). However, a response of greater magnitude was observed in old acyclic rats. Melatonin treatment reduced this increased response in acyclic rats and produced a pituitary responsiveness similar to that of young cyclic rats. FSH secretion was independent of GnRH administration in all groups, indicating desynchronization between LH and FSH secretion in response to GnRH in young animals and during senescence. No effect on prolactin was observed. Significantly higher LH (3009.11 +/- 1275.08 pg ml(-1); P < 0.05) and FSH concentrations (5879.28 +/- 1631.68 pg ml(-1); P < 0.01) were seen in acyclic control rats. After melatonin treatment, LH (811.11 +/- 89.71 pg ml(-1)) and FSH concentrations (2070 +/- 301.62 pg ml(-1)) decreased to amounts similar to those observed in young cyclic rats. However, plasma concentrations of oestradiol and progesterone were not reduced. In conclusion, the results of the present study indicate that, during ageing, the effect of melatonin is exerted primarily at the hypothalamo-pituitary axis rather than on the ovary. Melatonin restored the basal concentrations of pituitary hormones and pituitary responsiveness to similar values to those observed in young rats.

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