Dive into a comprehensive 28-minute lecture on receptor pathways in endocrinology. Explore the intricacies of peptide and steroid hormones, delving into G protein-coupled receptors and inhibition mechanisms. Learn about various hormone types, second messenger systems, and specific pathways including G stimulatory, GQ, and G inhibitory. Understand the role of oxytocin in muscle contraction and examine steroid hormone pathways. Benefit from a structured presentation with a detailed table of contents, covering key concepts in endocrinology. Note the correction regarding phosphodiesterase and phospholipase C for accurate understanding.