Effects of morphine on sprouting of locus coeruleus fibers in the neonatal rat

Buprenorphine potentiates L-DOPA-induced contralateral rotation in 6-hydroxydopamine-treated rats

Animals are commonly given opioid analgetics such as buprenorphine for post-operative pain management. In this study, the effect of the analgetic buprenorphine, a partial mu receptor agonist and kappa receptor antagonist, on L-DOPA-induced contralateral rotation was measured in 6-hydroxydopamine (6-OHDA) treated rats. Male Sprague-Dawley rats received dopamine-depleting brain lesions by infusion of 6-OHDA into the medial forebrain bundle. After the procedure, buprenorphine was administered (430 microg/kg, s.c.) to 17 of 54 animals. Three weeks after 6-OHDA treatment, animals were given benserazide HCI (25 mg/kg, i.p.) and L-DOPA (4 mg/kg, i.p.). Contralateral rotations were monitored for 2 h. Animals receiving buprenorphine had significantly higher rates of rotation as compared with non-buprenorphine-treated animals (P = 0.023). The results suggest that buprenorphine sensitizes animals to the effects of L-DOPA.

Prenatal stress has long-term effects on brain opiate receptors

Prenatal stress has been associated with a number of behavioral consequences including altered sensitivity to exogenous opiates. In the present study, mu opiate receptors were compared in the 42-day-old offspring from females stressed on days 15-22 of gestation and from females who were unstressed controls. Membrane homogenates from the prenatal stress group showed less binding of the mu opiate receptor ligand, [3H]DAGO in striatum but not in several other brain regions. Saturation studies suggest this difference is due to fewer striatal mu opiate receptors in offspring of prenatally stressed females. Using in vitro receptor autoradiography, the decreased binding in striatum was found mostly in the rostral striatum, extending into the nucleus accumbens with conservation of the normal anatomic distribution of receptor rich patches.

Opioids and the developing organism: a comprehensive bibliography, 1984-1988

A comprehensive bibliography of the literature concerned with opioids and the developing organism for 1984-1988 is presented. Utilized with companion papers (Neurosci. Biobehav. Rev. 6:439-479; 1982; 8:387-403; 1984), these articles cover the clinical and laboratory references beginning in 1875. For the years 1984, 1985, 1986, 1987, and 1988, a total of 877 citations were recorded. A series of indexes accompanies the citations in order to make the literature more accessible. These indexes are divided into clinical and laboratory topics, and subdivided into such topics as the type of opioid explored and the general area of biological interest (e.g., physiology).