The effect of morphine on melatonin secretion in the domestic pig. In vivo and in vitro study. Lewczuk B, Przybylska-Gornowicz B, Wyrzykowski Z. Journal Article 1999; 20(3-4): 171-178 PubMed PMID: 11462111 Citation : Up till now the results of performed investigations suggest the involvement of opioids in the regulation of the pineal gland activity in..... Read abstract Full text PDF