Neonatal 6-hydroxydopamine sympathectomy in normotensive and spontaneously hypertensive rat

• Published in: Pharmacology, biochemistry and behavior Vol. 2; no. 3; pp. 381 - 386
• Main Authors: Pappas, B.A., Peters, D.A.V., Saari, M., Sobrian, S.K., Minch, E.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.05.1974
• Subjects: 6-OHDA; Activity; Adrenal Glands - enzymology; Analysis of Variance; Animals; Animals, Newborn; Behavior - drug effects; Behavior, Animal; Blood Pressure; Brain - metabolism; Brain Stem - metabolism; Carbon Radioisotopes; Chromatography, Ion Exchange; Dihydroxyphenylalanine - metabolism; Emotionality; Female; Ganglia, Autonomic - drug effects; Ganglia, Autonomic - physiology; Ganglia, Autonomic - physiopathology; Hydroxydopamines - pharmacology; Hypertension - physiopathology; Male; Norepinephrine - metabolism; Rats; Serotonin - biosynthesis; Spontaneous hypertension; Sympathectomy; Time Factors; Tyrosine 3-Monooxygenase - metabolism; Emotionality; 6-OHDA; Activity; Sympathectomy; Spontaneous hypertension
• DOI: 10.1016/0091-3057(74)90084-7
• ISSN: 0091-3057

Neonatal sympathectomy was produced in rats from either a normotensive or spontaneously hypertensive (SHR) strain by repeated s.c. injections of hydroxydopamine (6-OHDA). The SHR rats were considerably more active than the normotensive rats in the open field and activity wheels. Emotionality, defined by the profile of open field activity and defecation scores, was lower in the SHR. Neonatal 6-OHDA had no effect upon emotionality or running wheel activity. Adult endogenous brain norepinephrine was increased in brainstem and decreased in cortex of both strains by 6-OHDA. Tyrosine hydroxylase activity in the brains of normotensive, 6-OHDA injected rats varied directly with altered endogenous NE levels. Preliminary data also indicated increased serotonin synthesis in the brainstem of 6-OHDA injected rats. It was concluded that neonatal injections of 6-OHDA may cause selective degeneration of the descending and dorsal NE brain pathways, and that the behavioral effects of this treatment, while yet obscure, seem to resemble those produced by hippocampal lesions.