Anaesthesia with alphaxalone plus alphadolone acetate decreases serum concentrations of LH in castrated rats

Abstract

Alphaxalone is considered the anaesthetic of choice in neuroendocrine reproductive studies in female rats, since it appears to have little, if any, effect on release of gonadotrophin-releasing hormone. There has been less study of the effects of this anaesthetic on the male reproductive neuroendocrine axis, however. Accordingly, the time-dependent effects of alphaxalone, as well as of urethane and ketamine, on the increased levels of LH in castrated rats were determined. Each anaesthetic was administered i.p. and each depressed LH levels significantly compared with those in castrated unanaesthetized rats killed by decapitation (controls). The effect of the anaesthetics was noted 15 min after administration and persisted at 30 and 60 min in animals anaesthetized with alphaxalone and urethane. Only in ketamine-anaesthetized animals did serum concentrations of LH finally rise to concentrations not significantly different from those in control rats. Thus alphaxalone, though useful in female neuroendocrine studies, is as profoundly disruptive as other anaesthetics on the male rat hypothalamic-pituitary reproductive unit.

Ketamine attenuates cytochrome p450 aromatase gene expression and estradiol‐17β levels in zebrafish early life stages

“…Anesthetics have complex neuroendocrine effects and ketamine is known to block spontaneous GnRH (gonadotropin-releasing horomone) release and to decrease peripheral LH levels in adult rats (Cohen et al, 1983;Emanuele et al, 1987;Matzen et al, 1987;Sherwood et al, 1980). However, in male Sprague-Dawley rats, ketamine treatment increased testosterone concentrations, but decreased LHRH (luteinizing hormone-releasing hormone) after 1 of administration and continued to significantly decrease after 24 h (Gould, 2008).…”