BACKGROUND Cannabinoid receptor agonists reverse nausea and vomiting produced by chemotherapy and radiation therapy in animals and humans but have not been tested against opioid-induced emesis. This study tests the hypothesis that cannabinoid receptor agonists will prevent opioid-induced vomiting. METHODS Twelve male ferrets were used. They weighed 1.2-1.6 kg at the beginning and 1.8-2.3 kg a...

The effect of delta9-tetrahydrocannabinol (THC), the major psycho-active component of marijuana, in human prostate cancer cells PC-3 was investigated. THC caused apoptosis in a dose-dependent manner. Morphological and biochemical changes induced by THC in prostate PC-3 cells shared the characteristics of an apoptotic phenomenon. First, loss of plasma membrane asymmetry determined by fluorescent...

To date, the endogenous ligands described for cannabinoid receptors have been derived from membrane lipids. To identify a peptide ligand for CB(1) cannabinoid receptors, we used the recently described conformation-state sensitive antibodies and screened a panel of endogenous peptides from rodent brain or adipose tissue. This led to the identification of hemopressin (PVNFKFLSH) as a peptide liga...

Nuclear factor (NF)-κB is the key transcription factor involved in the inflammatory responses, and its activation aggravates tumors. Peptidoglycan (PGN), a main cell wall component of Gram-positive bacteria, stimulates Toll-like receptor 2 (TLR-2) and activates a number of inflammatory pathways, including NF-κB. Cannabinoids have been reported to ...

Previous studies using a rat 5-choice serial reaction time task have established a critical role for dopamine D2 receptors in regulating increments in motor impulsivity induced by acute administration of the psychostimulant drugs amphetamine and nicotine. Here we investigated whether cannabinoid CB1 and/or μ-opioid receptors are involved in nicotine-induced impulsivity, given recent findings in...

Singing by adult male zebra finches is a learned behavior important for courtship, kin recognition, and nest defense (Zann, 1996) and is inhibited by both brief periods of limited food availability and systemic injection of cannabinoids. These similar effects on singing, combined with increasing evidence for endocannabinoid involvement in feeding behavior, led us to evaluate a possible shared m...

The effect of cannabinoids on the excitatory input to the substantia nigra reticulata (SNr) from the subthalamic nucleus was explored. For this purpose a knife cut was performed rostral to the subthalamic nucleus to isolate the subthalamic nucleus and the SNr from the striatum, a major source of cannabinoid receptors to the SNr. The data showed that the cannabinoid agonist WIN55,212-2 blocked t...

Systemically administered cannabinoids elicit marked cardiovascular effects, and the role of the central and the peripheral nervous system in these effects is not clarified. The aim of this study was to characterize the actions of cannabinoids on cardiovascular regulatory centers in conscious rabbits. A catheter for administration of drugs into the cisterna cerebellomedullaris and an electrode ...

CB(1) cannabinoid receptors mediate profound hypothermia when cannabinoid agonists are administered to rats. Glutamate, the principal excitatory neurotransmitter in the central nervous system (CNS), is thought to tonically increase body temperature by activating N-methyl-D-aspartate (NMDA) receptors. Because NMDA antagonists block cannabinoid-induced antinociception and catalepsy, intimate glut...

The effects of cannabinoids on the baroreflex have been investigated in the nucleus tractus solitarii (NTS). In urethane-anesthetized rats, microinjection of the cannabinoid (CB) receptor agonist WIN 55212-2 (100 mM) into the NTS produced a short lasting decrease in arterial pressure (from 95.2 ± 2.9 to 76.2 ± 1.5, n=5, P<0.05) but no change in the heart rate. Another cannabinoid agonist, CP 55...