Preventing and reversing opioid dependence continues to be a clinical challenge and underlying mechanisms of opioid actions remain elusive. We report that matrix metalloproteinase-9 (MMP-9) in the spinal cord contributes to development of physical dependence on morphine. Chronic morphine exposure and naloxone-precipitated withdrawal increase activity of spinal MMP-9. Spinal inhibition or target...

Tolerance and dependence are two main problems that have limited morphine administration. There are several reports on the effect of some medicinal plants on morphine-induced tolerance and dependence. In this study we investigated the effect of Ferula persica (FP) extract on modulation of withdrawal syndrome sign (WSS). For this purpose, male Albino mice (25-30 g, n=30) were used. Morphine was ...

Tolerance and dependence are two main problems that have limited morphine administration. There are several reports on the effect of some medicinal plants on morphine-induced tolerance and dependence. In this study we investigated the effect of Ferula persica (FP) extract on modulation of withdrawal syndrome sign (WSS). For this purpose, male Albino mice (25-30 g, n=30) were used. Morphine was ...

Effect of Otostegia persica on naloxone-induced morphine withdrawal syndrome was studied in male mice. Dependence was induced using daily subcutaneous injections of morphine for three days. Morphine was injected to mice at doses of 30 and 45mg/kg on day 1 and 60 and 90mg/kg on day 2 (8:00 am and 6:00 pm). On day 3, morphine (90mg/kg) was injected 1h before oral administration and 1.5h before in...

The purpose of this study was to evaluate whether berberine (BER) administration could attenuate depression- and anxiety-like behaviors and increase corticotrophin-releasing factor (CRF) and tyrosine hydroxylase (TH) expression following chronic morphine withdrawal in rats. Male rats were exposed to chronic, intermittent, escalating morphine (10~50 mg/kg) for 10 days. After the last morphine in...

Opiate abuse causes adaptive changes in several processes of synaptic transmission in which the glutamatergic system appears a critical element involved in opiate tolerance and dependence, but the underlying mechanisms remain unclear. In the present study, we found that glutamate uptake in hippocampal synaptosomes was significantly increased (by 70% in chronic morphine-treated rats) during the ...

It has been suggested that an increase firing rate of noradrenergic neurons of the locus ceruleus is responsible for the opiate withdrawal syndrome. However, lesion studies have indicated that the noradrenergic neurons of the locus ceruleus are not essential for either the expression or suppression by clonidine of opiate withdrawal. The present study was designed to determine the effect of the ...

The possibility that pain perception and processing in the CNS results in cellular stress and may influence heat shock protein (HSP) expression was examined in a rat model of morphine dependence and withdrawal. Since activation of pain pathways result in exhaustion of growth factors, we examined the influence of cerebrolysin, a mixture of potent growth factors (BDNF, GDNF, NGF, CNTF etc,) on mo...

Chronic use of morphine leads to physical and psychological dependence. The amygdala is known to be involved in the expression of emotion such as anxiety and fear, and several studies have shown that the central nucleus of the amygdala (CeA) is involved in morphine dependence. In the present study, we investigated the role of glutamate receptors within the CeA in the negative affective componen...

The opponent-process theory of motivation postulates that motivational stimuli activate a rewarding process that is followed by an opposed aversive process in a homeostatic control mechanism. Thus, an acute injection of morphine in nondependent animals should evoke an acute rewarding response, followed by a later aversive response. Indeed, the tegmental pedunculopontine nucleus (TPP) mediates t...