Experimental studies on the acetylcholinesterase‐positive nerves in the ovary of the rat

Adrenergic and acetylcholinesterase (AChE)‐positive nerves were studied in the rat ovary four days after various experimental denervation procedures. Ablation of pelvic parasympathetic nerves (pelvic neurectomy [PN]) or abdominal vagotomy (AV) had no obvious affect on the adrenergic or AChE‐positive nerves in the ovary. Section of the mesovarium resulted in the loss of all histochemically demonstrable adrenergic and AChE‐positive nerves. Chemical sympathectomy with 6‐hydroxydopamine (6‐HD) resulted in the loss of all histo‐chemically demonstrable adrenergic nerves. A few AChE‐positive nerves remained in the hilar and medullary regions following chemical sympathectomy. When the presumptive parasympathectomy procedures (AV and PN) were combined with chemical sympathectomy, again no adrenergic nerves remained, however a few hilar and medullary AChE‐positive fibers persisted after sympathec‐tomy plus PN, but no AChE‐positive fibers were demonstrable in the AV plus 6‐HD group. These findings show that most of the AChE in ovarian nerves is localized in adrenergic nerves. It is suggested that the few AChE‐positive fibers remaining in the ovarian hilar area after 6‐HD treatment or 6‐HD plus PN are derived from the vagus. These few AChE‐positive nerves may be postganglionic vagal parasympathetic or they may be sensory fibers.