Differential roles of corticotropin-releasing factor receptor subtypes 1 and 2 in opiate withdrawal and in relapse to opiate dependence

2000 ◽  
Vol 12 (12) ◽  
pp. 4398-4404 ◽  
Author(s):  
Lin Lu ◽  
Dehong Liu ◽  
Xiabo Ceng ◽  
Lan Ma
1993 ◽  
Vol 33 (4) ◽  
pp. 285-290 ◽  
Author(s):  
S E Davison ◽  
D M Forshaw

We note growing concern by defence councils over the reliability of confessions obtained from suspects withdrawing from opiate dependence. We focus on a case report and highlight the conceptual weaknesses of current thinking about confessions. A philosophical model is adapted to clarify the theoretical aspects and thereby provide a conceptual framework to help the doctor confronted with the practical issue of how to assess a suspect's fitness for interrogation or the reliability of an individual's confession. We argue that the practice of not treating withdrawal in custody is unjust and inhumane. The model presented is of value in dealing with the issues raised by retracted confessions generally and not just in the specific instances where the suspect is a drug user.


2008 ◽  
Vol 295 (6) ◽  
pp. R1762-R1773 ◽  
Author(s):  
Christina Chotiwat ◽  
Ruth B. S. Harris

Rats exposed to 3 h of restraint stress on each of 3 days (RRS) lose weight on the days of RRS and gain weight at the same rate as controls after stress ends, but do not return to the weight of controls. RRS rats also show an exaggerated endocrine response to subsequent novel stressors. Studies described here tested the effects of corticotropin-releasing factor receptor (CRFR) antagonism on RRS-induced weight loss, hypophagia, and corticosterone release during mild stress in the postrestraint period. Weight loss was not prevented by either peripheral or third-ventricle administration of a CRFR1 antagonist, antalarmin, before each restraint. Antalarmin did, however, allow recovery of body weight in the poststress period. Third-ventricle administration of a CRFR2 antagonist, antisauvagine 30, had no effect in RRS rats but caused sustained weight loss in control animals. Surprisingly, third-ventricle administration of the nonselective CRFR antagonist, astressin, caused hypophagia and reversible weight loss in control rats. It had no effect in RRS rats. None of the antagonists modified the corticosterone response to RRS or to mild stress in the post-RRS period, but antalarmin suppressed corticosterone during the period of restraint in Control rats. These results suggest that CRFR1 activation is required for the initiation of events that lead to a prolonged down-regulation of body weight in RRS rats. The sustained reduction in body weight is independent of the severity of hypophagia on the days of restraint and of RRS-induced corticosterone release.


2021 ◽  
Author(s):  
Shaaban Mousa ◽  
Mohammed Shaqura ◽  
Baled Khalefa ◽  
Li Li ◽  
Mohammed Al-madol ◽  
...  

Abstract Corticotropin-releasing factor (CRF) orchestrates our body’s response to stressful stimuli. Pain is often stressful and counterbalanced by activation of CRF receptors along the nociceptive pathway, although the involvement of the CRF receptors of subtypes 1 and/or 2 (CRF-R1 and CRF-R2, respectively) in CRF-induced analgesia remains controversial. This study aimed to examine CRF-R1 and CRF-R2 expression within spinal cord of rats with Freund’s complete adjuvant-induced hindpaw inflammation using reverse transcriptase polymerase chain reaction, Western blot, radioligand binding, and immunofluorescence confocal analysis, Western blot, immunohistochemistry, and radioligand binding. Moreover, paw pressure algesiometry examined antinociceptive effects of intrathecal (i.t.) CRF and their possible antagonism through CRF-R1 and/or CRF-R2 selective antagonists as well as opioid receptor antagonist naloxone. Our results demonstrated mainly CRF-R2 mRNA, protein, binding sites and immunoreactivity in dorsal horn of rat spinal cord. In parallel, i.t. CRF as well as CRF-R2 agonists elicited potent antinociceptive effects which are dose-dependent and antagonized exclusively by i.t. CRF-R2 (K41498), but not CRF-R1 (NBI35965) antagonist. Moreover, i.t. CRF elicited inhibition of somatic pain that was dose-dependently reversed by the opioid antagonist naloxone. Consistently, double immunofluorescence confocal microscopy showed CRF-R2 on enkephalin (ENK) containing inhibitory interneurons in close opposition of incoming, mu-opioid receptor-immunoreactive nociceptive neurons but not on pre- nor on postsynaptic sensory neurons of the spinal cord. Taken together, these findings suggest that i.t. CRF or CRF-R2 agonist inhibits inflammatory somatic pain which occurs most predominantly through CRF-R2 receptors located on spinal enkephalinergic inhibitory interneurons resulting in endogenous opioid-mediated pain inhibition.


CNS Spectrums ◽  
2018 ◽  
Vol 23 (1) ◽  
pp. 107-107 ◽  
Author(s):  
Stefany Kress ◽  
Alan Hirsch

AbstractINTRODUCTIONBuprenorphine/Naloxone combination drugs such as Suboxone and Bunavail have not been reported to induce glycolimia. Two such cases are presented.METHODSCASE STUDY: Case 1: A 30-year-old, right-handed, white female with a history of opioid abuse was started on 4.2 mg buprenorphine/0.7 mg naloxone (Bunavail) BID and began sweet cravings and consumption of sweet foods. In a typical day she would eat 16 strawberry pop-tarts and 2 boxes of Little Debbie cookies. This may have provoked the 10 pound weight augmentation in the first two weeks of treatment. She denied any craving for opioids and no evidence of opioid withdrawal was present. Her Clinical Opiate Withdrawal Scale (COWS) score =4 (normal).Case 2: A 51-year-old, right-handed, male with opiate dependence, four days following the initiation of Suboxone (8 mg buprenorphine/2 mg naloxone) BID, developed strong cravings for sugary foods including donuts and ice cream, of which he was previously never inclined to eat and gained 10 pounds in one month. His COWS score= 7 (mild symptoms).DISCUSSIONThere are myriad mechanisms that may be acting to induce sugar cravings with buprenorphine/naloxone. Humans and rats acutely withdrawing from opiates, such as heroin, develop strong urges for consumption of sugary substances (Lieblich et al., 1991; Sapira, 1968; Weiss, 1982). Glycolimia in the above cases may reflect early or subclinical withdrawal, which if becoming more severe, would manifest as opioid craving. If the value of the reward system induced by sweets doesn’t meet the threshold invoked by the opioid stimulation, this “withdrawal” may lead to further sugar cravings in an attempt to reach the same reward level. In animals, certain foods and drugs share the same neurological pathway involved in the “reward system” potentially explaining why opioids influence food palatability in humans (Pelchat, 2002).Alternatively, it is possible that buprenorphine induces hypoglycemia at high doses (Bullingham et al., 1981) such that hypoglycemia may paradoxically act to enhance sugar craving similar to the Somogyi effect in insulin dependent diabetics. Another possible mechanism of action is that since buprenorphine acts to decrease glucose metabolism in the brain (Walsh et al., 1994), this may lead to a neural compensatory response by increasing sugar access to the brain behaviorally via glycolimiaand somatically reducing insulin release, thus explaining the high hemoglobin A1c observed in opioid addicts (Giugliano, 1984). Given the above presentation, complaints of sugar craving may indicate consideration to increase buprenorphine dosing and trial of this in those with glycolimia without opioid dependence may be warranted.Funding AcknowledgementsNo funding.


2009 ◽  
Vol 66 (1) ◽  
pp. 76-83 ◽  
Author(s):  
Maria Waselus ◽  
Cristiano Nazzaro ◽  
Rita J. Valentino ◽  
Elisabeth J. Van Bockstaele

Endocrinology ◽  
2012 ◽  
Vol 153 (12) ◽  
pp. 5701-5705 ◽  
Author(s):  
Jill M. Weathington ◽  
Bradley M. Cooke

Abstract Corticotropin-releasing factor receptors type 1 (CRF1) and type 2 (CRF2) have complementary roles in controlling the hypothalamic-pituitary-adrenal (HPA) axis. Because CRF receptors are expressed in sex steroid-sensitive areas of the forebrain, they may contribute to sex-specific patterns of stress sensitivity and susceptibility to stress-related mood disorders, which are more frequent in women. To determine whether CRF receptors vary as a function of age and/or sex, we measured receptor binding in the amygdala of male and female, prepubertal and adult rats. Both receptor subtypes demonstrated age- and sex-specific binding patterns. In the basolateral amygdala and posteroventral medial amygdala, CRF1 binding decreased in males and increased in females after puberty, there, CRF2 binding increased in males and was unchanged in females. In the posterodorsal medial amygdala, CRF1 binding was unchanged across puberty, whereas CRF2 binding increased across puberty far more in males than in females. Binding was lowest overall in the central amygdala; there, CRF1 was unchanged while CRF2 binding increased across puberty only in males. Thus, in all four examined areas across prepuberty to adulthood, CRF2 binding increased far more in males than in females and resulted in significantly more binding in adult males than in adult females. These sex-specific developmental patterns are consistent with sex differences in hypothalamic-pituitary-adrenal responsiveness and may thus contribute to sex differences in mood disorder susceptibility.


2021 ◽  
Author(s):  
Shaaban A. Mousa ◽  
Mohammed Shaqura ◽  
Baled Khalefa ◽  
Li Li ◽  
Mohammed Al-madol ◽  
...  

Abstract Background: Corticotropin-releasing factor (CRF) orchestrates our body’s response to stressful stimuli. Pain is often stressful and counterbalanced by activation of CRF receptors along the nociceptive pathway, although the involvement of the CRF receptors of subtypes 1 and/or 2 (CRF-R1 and CRF-R2, respectively) in CRF-induced analgesia remains controversial.Methods: This study aimed to examine CRF-R1 and CRF-R2 expression within spinal cord of rats with Freund’s complete adjuvant-induced hindpaw inflammation using reverse transcriptase polymerase chain reaction, Western blot, radioligand binding, and immunofluorescence confocal analysis, Western blot, immunohistochemistry, and radioligand binding. Moreover, paw pressure algesiometry examined antinociceptive effects of intrathecal (i.t.) CRF and their possible antagonism through CRF-R1 and/or CRF-R2 selective antagonists as well as opioid receptor antagonist naloxone.Results: Our results demonstrated mainly CRF-R2 mRNA, protein, binding sites and immunoreactivity in dorsal horn of rat spinal cord. In parallel, i.t. low, systemically inactive doses of CRF as well as CRF-R2 agonists elicited potent antinociceptive effects which are dose-dependent and antagonized exclusively by i.t. CRF-R2 (K41498), but not CRF-R1 (NBI35965) antagonist. Moreover, i.t. CRF elicited inhibition of somatic pain that was dose-dependently reversed by the opioid antagonist naloxone. Consistently, double immunofluorescence confocal microscopy showed CRF-R2 on enkephalin (ENK) containing inhibitory interneurons in close opposition of incoming, mu-opioid receptor-immunoreactive nociceptive neurons but not on pre- nor on postsynaptic sensory neurons of the spinal cord.Conclusion: Taken together, these findings suggest that i.t. CRF or CRF-R2 agonist inhibits inflammatory somatic pain which occurs most predominantly through CRF-R2 receptors located on spinal enkephalinergic inhibitory interneurons resulting in endogenous opioid-mediated pain inhibition.


2021 ◽  
Author(s):  
Shaaban Mousa ◽  
Mohammed Shaqura ◽  
Baled khalefa ◽  
Li Li ◽  
Mohammed Al-madol ◽  
...  

Abstract Corticotropin-releasing factor (CRF) orchestrates our body’s response to stressful stimuli. Pain is often stressful and counterbalanced by activation of CRF receptors along the nociceptive pathway although the involvement of the CRF receptor subtypes 1 and/or 2 (CRF-R1 and CRF-R2, respectively) in CRF-induced analgesia remains controversial. This study examined CRF-R1 and CRF-R2 expression within the spinal cord of rats with Freund’s complete adjuvant-induced hindpaw inflammation using reverse transcriptase polymerase chain reaction, Western blot, radioligand binding, and immunofluorescence confocal analysis. Moreover, paw pressure algesiometry examined antinociceptive effects of intrathecal (i.t.) CRF and their possible antagonism through CRF-R1 and/or CRF-R2 selective antagonists as well as the opioid receptor antagonist naloxone. Our results demonstrated predominantly CRF-R2 mRNA, protein, binding sites and immunoreactivity in the dorsal horn of the rat spinal cord. Consistently, CRF as well as CRF-R2 agonist elicited potent, dose-dependent anti-nociceptive effects which were antagonized selectively by i.t. CRF-R2 (K41498) antagonist but not by CRF-R1 (NBI35965) antagonist. Moreover, the opioid antagonist naloxone dose-dependently reversed the i.t. CRF- as well as CRF-R2 agonist-elicited inhibition of somatic pain. Supporting these findings, double immunofluorescence confocal microscopy showed CRF-R2 on enkephalin (ENK)-containing inhibitory interneurons in close opposition of incoming mu-opioid receptor-immunoreactive nociceptive neurons. CRF-R2 was, however, not seen on pre- or on postsynaptic sensory neurons of the spinal cord. Taken together, these findings suggest that i.t. CRF or CRF-R2 agonist inhibit inflammatory somatic pain, occurring predominantly through CRF-R2 receptors located on spinal enkephalinergic inhibitory interneurons, which results in endogenous opioid-mediated pain inhibition.


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