The effect of surgical sympathectomy and of neonatal treatment with 6‐hydroxydopamine and guanethidine on particle‐bound noradrenaline and35S‐sulphomucopolysaccharides

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Abstract
Five to six weeks after bilateral stellate ganglionectomy, noradrenaline (NA) levels in cats' atria were reduced to ∽ 20% of controls. In vivo uptake of3H‐NA and of35S‐sulphate into gradient fractions containing noradrenergic vesicles from the atria decreased to ∽30% and ∽40%, respectively. The uptakes of3H‐NA and35S‐sulphate were significantly correlated in both control and ganglionectomized cats, and the distributions of3H and35S on the gradients were parallel. The findings suggest that sulphomucopolysaccharides (SMPSs) may be localized in noradrenergic vesicles, possibly participating in the storage of NA. In 10‐week‐old rats treated neonatally with either 6‐hydroxydopamine (6‐OH‐DA) or guanethidine, levels of NA in the heart, spleen and salivary glands were decreased to 3H‐NA uptake into noradrenergic‐vesicle‐enriched subcellular fractions from the heart, spleen and salivary glands of 6‐OH‐DA treated rats decreased almost to the extent of NA depletion but in the seminal ducts the decrease was less marked. Guanethidine treatment left the uptake unaffected, except for the spleen. The discrepancy between storage and uptake suggests that surviving neurons display during their outgrowth into tissues a high uptake capacity but lack full NA synthesis.35S‐sulphate incorporation into non‐lipid compounds, presumably SMPSs, in the noradrenergic‐vesicle‐enriched fractions appeared unaffected or increased over corresponding control levels, possibly due to high synthetic activity in the growing neurons.