MARKED INCREASES IN NEURONAL NITRIC-OXIDE SYNTHASE (NNOS) MESSENGER-RNA AND NADPH-DIAPHORASE HISTOSTAINING IN ADRENAL-CORTEX AFTER IMMOBILIZATION STRESS IN RATS

The changes of neuronal nitric oxide synthase (nNOS) mRNA expression i n the rat adrenal gland following immobilization-induced stress were e xamined by the in situ hybridization technique. To introduce immobiliz ation stress, the animals were wrapped with flexible wire gauze for 6 h. In the adrenal medulla and cortex, signals for nNOS mRNA were detec ted. In the adrenal medulla, the difference between non-stressed and s tressed animals was not clear. In the adrenal cortex, the expression o f nNOS mRNA markedly increased (2.5-fold) in the stressed animals. Nic otinamide adenine dinucleotide phosphate-diaphorase (NADPH-diaphorase) histochemistry also showed an increase of staining in adrenal cortex after stress. This suggests that nitric oxide (NO) is involved in stre ss-induced activation in adrenal cortex function. Copyright (C) 1996 E lsevier Science Ltd.