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J J Curry

Publications and source records attributed to J J Curry.

At least 19 recordsLinked to original sources
PubMed1984

The role of neurotransmitters in mediating copulation-induced ovulation in the rat.

Pentobarbitone-blocked pro-oestrous rats were subjected to either limited mating (maximum of 30 mounts), all-night cohabitation with males or stimulation of the vagina and cervix with a glass rod (2 or 5 min) to determine which type of stimulus was most effective in inducing ovulation. All-night cohabitation was the most successful procedure and resulted in 100% ovulation in those rats which mated. Treatment with either phenoxybenzamine, propranolol or pimozide did not interfere with this copulation-induced ovulation whereas methysergide treatment completely blocked copulation-induced ovulation. Administration of atropine resulted in a loss of mating behaviour and these animals therefore did not ovulate. Further experiments provided evidence that administration of atropine also blocked ovulation in response to vaginal stimulation with a glass rod. Pretreatment with methysergide or atropine had no effect upon the percentage of pentobarbitone-blocked, pro-oestrous rats ovulating in response to administration of LH releasing hormone (LHRH). However, those rats given atropine shed significantly fewer ova per rat following LHRH or LH infusion when compared with controls. These results suggest that the synaptic mechanisms responsible for mediating copulation-induced ovulation are different from those mediating steroid-induced ovulation, and that ovarian cholinergic receptors may play a role in ovulation.

Animals↗
PubMed1983

Preliminary evidence for a CNS site of action for ovarian inhibin.

The ovariectomized rat bearing estrogen-containing silastic capsules underwent a primary FSH rise at 1700 hrs on all days studied. A more prolonged secondary FSH rise also occurs beginning at 2100 hrs. The primary FSH rise was attenuated or blocked by injection of charcoal-extracted porcine follicular fluid (pFF) or an extract of pFF (pFFX) limited to substances having molecular weights between 10,000 and 30,000 d. Application of pFFX directly to the dorsal anterior hypothalamic area (dAHA) by means of chronically implanted cannulas resulted in attenuation of the primary FSH rise. Similar application to medial preoptic area (mPOA) was without effect. These findings suggest that an active FSH suppressing agent, presumably ovarian inhibin, may be acting at least in part at the level of the central nervous system.

Animals↗
PubMed1980

The early development of corticobulbar and corticospinal systems. Studies using the North American opossum.

The North American opossum is born 12 days after conception and is therefore available for experimental manipulation in an immature state. We have used the opossum to study the growth of cortical axons into the brainstem and spinal cord and have obtained evidence that such growth occurs in an orderly fashion. Cortical axons reach the ventral mesencephalon 12 days after birth and some of them have grown into the caudal medulla where they decussate by 23 days. At the latter stage immature cortical axons also distribute to the midbrain tegmentum, the basilar pons, the inferior olive and the hilum of the nucleus cuneatus. Cortical axons first enter the spinal cord about 30 days after birth where they are present in the white matter before growing into the dorsal horn. The forelimb placing reaction does not develop until well after cortical axons have reached cervical levels. Axons from the cerebral cortex grow into the spinal cord before there is evidence for cortical innervation of either the red nucleus or the bulbar reticular formation and well before pyramidal cells of the neocortex are mature. The relatively late development of corticospinal and corticobulbar systems contrasts markedly with the early growth of bulbospinal axons.

Animals↗