A drug designed to inhibit the response of cells to testosterone would almost certainly result in which of the following? a. a decrease in G protein activity. b. a decrease in transcriptional activity of certain genes. c. an increase in receptor tyrosine kinase activity. d. lower cytoplasmic levels of cAMPe. an increase in cytosolic calcium concentration

b. a decrease in transcriptional activity of certain genes.

Explanation:

Testosterone is a lipid-soluble steroid hormone and is a derivative of cholesterol. Being a lipid-soluble hormone, it enters the target cells and binds to respective nuclear receptors. Receptors for steroid hormones such as testosterone are mostly transcription factors. Binding of testosterone to its receptors activates them. The activated transcription factors then bind to specific DNA sequences to increase the expression of certain sets of genes.

A drug that inhibits the cellular response towards testosterone would not allow upregulation of the target genes. Therefore, the cells would exhibit reduced expression of certain sets of genes that are otherwise expressed at a higher rate in the response to testosterone.

B

Explanation:

Decrease transcriptional expression of certain genes.