This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: General physiology, Subject name: Physiology
A primigravida with 38 completed weeks of gestation has gone into labor. Oxytoxin was staed to augment labor. The second messenger system through which oxytoxin acts is ? 
Select and explain. 
A. cAMP, B. Phospholipase, C. cGMP, D. Tyrosine kinase
B: Phospholipase
Answer: B: Phospholipase 
Explanation: The second messenger system through which oxytoxin acts in phospoholipase C mechanism. Hormones acting IP3- DAGor phospholipase C pathway: Acetylcholine (muscuranic) Angiotensin II ] ADH (V1 receptor ) a1 receptor adrenergic hormones Cholecystokinin Gastrin GnRH Oxytoxin TRH GHRH Substance P Ref: internet sources