Question

Scientists at MN-Pharm Sci have identified a novel molecule with potent Mu-opioid receptor (MOR) agonist activity by using high throughput assays. Structurally, the molecule does not belong any of the known chemical classes. The affinity of the compound is 30-times higher at MORs compared to morphine with similar efficacy. The affinity of this molecule for recombinant human recombinant Kappa- and Delta-opioid receptors by 170– and 350–fold, respectively, lower than that observed at the recombinant human Mu-opioid receptors. The hydrophilic/lipophilic nature of the compound is comparable to morphine and protein binding is lower compared to morphine. In vivo studies revealed that the compound is metabolized by liver microsomal enzymes, and the metabolites have no affinity to opioid receptors and are free from toxicity in both mice and pigs. Drug distribution studies indicated that the compound is exclusively localized in periaqueductal gray matter (PAG) and spinal cord, and a very little or no localization observed in limbic structures. Peripheral distribution was similar to morphine.

Based on the preclinical studies as given above, predict the following pharmacological effects of this compound in comparison with morphine?

a. what is the name of the dug and Potential of causing euphoria

b. Potential of causing respiratory depression (vs morphine)

c. Potential of causing urinary retention

d. Safety in patients with hepatic cirrhosis

e. Safety in patients with nephropathy

Below is an example of how to answer the questions

[For example Analgesic effect of this molecule: This molecule is 30 times more potent than morphine in producing analgesia. It is likely to activate opioid receptors in PAG and dorsal gray horn of spinal cord to produce analgesia.]

Answer 1

a. Morphine is the drug which comes under opiods and causes the sense of euphoria.

b. The potential of causing respiratory distress is less as though the respiratory retention occurs but still the infrequent respiratory distress occurs and if done overdose naloxone is the drug given

C. The potential side effects would be urinary retention but not much incidence present than the decreased gastrointestinal motility

D. The opiods must be used carefully if the person is with liver cirrhosis as this may cause the worsening of the situation and should be used very cautiously.

E. When nephropathy is been diagnosed the morphine is contraindicated in the patients and hydromorphone or oxycodone is been used.