Final answer:
The α1 Receptor is responsible for the formation of IP3 and an increase in intracellular calcium levels when activated by adrenaline or noradrenaline.
Step-by-step explanation:
The adrenergic receptor that produces its stimulatory effects by the formation of inositol 1,4,5-triphosphate (IP3) and an increase in intracellular calcium ([Ca2+]) levels is the α1 Receptor. On the other hand, a2 receptors, B1 receptors, B2 receptors, muscarinic receptors, and nicotinic receptors do not produce their stimulatory effects through the formation of IP3 and an increase in intracellular calcium.
α1-adrenergic receptors are part of the G protein-coupled receptor superfamily and are activated by neurotransmitters adrenaline and noradrenaline. Upon activation by these ligands, the α1 receptors couple with the Gq protein, which activates phospholipase C (PLC). This in turn leads to an increased production of IP3 and diacylglycerol (DAG), with IP3 stimulating the release of calcium ions from intracellular stores, ultimately causing various physiological responses such as smooth muscle contraction.