A correlation analysis of the regional distribution of central enkephalin and beta-endorphin immunoreactive terminals and of opiate receptors in adult and old male rats. Evidence for the existence of two main types of communication in the central nervous system: the volume transmission and the wiring transmission.
By means of semiquantitative immunocytochemistry and quantitative receptor autoradiography a correlation analysis has been performed on the pre- and post-synaptic features of enkephalin and beta-endorphin immunoreactive neuron systems of the 3- and 24-month-old male rat. A parallel disappearance of enkephalin- and beta-endorphin-like immunoreactivity and of the density of mu and delta opiate receptors is shown during ageing. Furthermore, the lack of an overall correlation between the amount of pre- and post-synaptic components of the enkephalin and beta-endorphin synapses give evidence for the existence of a volume type of transmission in such systems in the telencephalic, diencephalic and mesencephalic areas analysed.
D000367:Age Factors; D000818:Animals; D001345:Autoradiography; D001921:Brain / Q000502:physiology*; D004723:Endorphins / Q000378:metabolism*; D004745:Enkephalins / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D008297:Male; D009411:Nerve Endings / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011957:Receptors, Opioid / Q000378:metabolism*; D009435:Synaptic Transmission; D001615:beta-Endorphin
D004723:Endorphins; D004745:Enkephalins; D011957:Receptors, Opioid; D001615:beta-Endorphin