Effects of the Neurointermediate Pituitary Lobectomy (NIL) on Pituitary Hormones Blood Level in the Rat

Abstract

The characterization of the functional state of the NIL animals is important to know all the possible physiological implications of the permanent deficiency of the hormones arginine vasopressin (AVP) and oxytocin (OT). In order to obtain knowledge of the unknown relationships of the effects of NIL on pituitary hormones blood level (GH, PRL, ACTH, TSH, LH, AVP and OT), as well as on urine production, water intake and body weight, groups of Intact Control (IC) and NIL male Wistar rats were compared at 3 and 8 weeks post‐surgery. Hormone levels were assessed by ELISA kits.ResultsNIL caused a transient diabetes insipidus; urine production and water intake returned to normal values between 2 to 4 weeks post‐NIL. AVP and OT serum levels in NIL rats were significantly decreased in 80% and 90% at 3 and 8 weeks post‐surgery. GH and TSH, were significantly decreased at 3 but not at 8 weeks post‐NIL. PRL and ACTH serum levels remained unchanged in both times. Final body weights of NIL animals were 20% less than the IC.ConclusionsNIL animals are a good experimental paradigm to study the protracted effects of AVP and OT deficiency. It is possible that the decreased GH serum levels NIL‐induced, caused the less gain of body weight of these animals.Support or Funding InformationSupported by CONACYT‐221262. México (AQS)