Developmental effect of dimethyl sulfoxide on hypothalamo‐neurohypophysial neurons in vitro

Abstract

Primary dissociated cultures were established from diencephalic tissue of 14-day-old fetal rats. Neurons exhibiting immunocytochemical staining for neurophsin appeared in these cultures after 6 days of cultivation. Addition of dimethyl sulfoxide (DMSO) to the culture medium resulted in a slight decrease in total neuronal cell mass as assessed by immunocytochemistry and radio-immunometric quantitation of neuron-specific enolase. In contrast, in DMSO-treated cultures the number of neurophysin-immunoreactive neurons was more than doubled as compared to control cultures. [³H] Thymidine labeling and autoradiography in conjuction with immunocytochemistry for neurophysin showed that this was not due to a mitogenic effect of DMSO on precursor cells. Time-course analysis of the action of DMSO revealed a 6-day time lag between the initiation of treatment and the appearance of increased numbers of neurophysin-immunoreactive cells. These findings suggest that DMSO, which has previously been on malignant transformed cells, may also modulate cellular processes that control differentiation in specific types of neurons in primary culture.