Alpha 1 Receptors
Adrenergic medications affect the four receptors, a1, a2, B1 and B2. The sympathetic nervous system triggers the secretion of epinephrine and norepinephrine. Epinephrine is a hormone and norepinephrine functions as a hormone and neurotransmitter.
First we will take a look at the Alpha 1 receptors. These Alpha 1 receptors cause vasoconstriction of vascular smooth muscles. They are located on the post synaptic membranes of effector organs, such as on gastral and urinary sphincters. Some are located on the dilator muscle of the iris causing the iris to dilate and reduce in size. You will also find them on the arrector pili muscle of hair follicles. They cause blood pressure to rise, increase peripheral resistance, cause vasoconstriction and increase …show more content…
They cause smooth muscle contractility and inhibit neurotransmitters from being released from the pre-synaptic neurons. They prevent norepinephrine from being released from adrenergic neurons and acetylcholine from being released from cholinergic neurons. On pancreatic beta cells, they hinder insulin from being released.
Beta 1 receptors are known as ADRB1, which is a G-protein coupled receptor, associated with the heterotrimeric G-protein, which is usually found in cardiac tissues. The Beta 1 receptors stimulate heart muscle contraction. Some of the effects it has on the body would be that it increases cardiac output, increases ventricular cardiac muscle by increasing contractility and atomicity. These receptors are also present in the cerebral cortex. They are located on cardiac pacemakers, on the myocardium, in salivary duct glands and in sweat glands. (Adrenergic Receptors, 2016).
Beta 2 has its primary receptors in the gastro tract, urinary bladder, bronchial tree and in the skeletal muscle arteries. They dilate the vessels so that they can receive increased blood flow when epinephrine is present. They also stimulate the smooth muscles of the bronchioles of the lungs, allowing more air flow. In the gastrointestinal tract, they can be found in the small intestine stomach, colon and rectum. They effect muscle tone to enable greater filling. (Upchurch,
First we will take a look at the Alpha 1 receptors. These Alpha 1 receptors cause vasoconstriction of vascular smooth muscles. They are located on the post synaptic membranes of effector organs, such as on gastral and urinary sphincters. Some are located on the dilator muscle of the iris causing the iris to dilate and reduce in size. You will also find them on the arrector pili muscle of hair follicles. They cause blood pressure to rise, increase peripheral resistance, cause vasoconstriction and increase …show more content…
They cause smooth muscle contractility and inhibit neurotransmitters from being released from the pre-synaptic neurons. They prevent norepinephrine from being released from adrenergic neurons and acetylcholine from being released from cholinergic neurons. On pancreatic beta cells, they hinder insulin from being released.
Beta 1 receptors are known as ADRB1, which is a G-protein coupled receptor, associated with the heterotrimeric G-protein, which is usually found in cardiac tissues. The Beta 1 receptors stimulate heart muscle contraction. Some of the effects it has on the body would be that it increases cardiac output, increases ventricular cardiac muscle by increasing contractility and atomicity. These receptors are also present in the cerebral cortex. They are located on cardiac pacemakers, on the myocardium, in salivary duct glands and in sweat glands. (Adrenergic Receptors, 2016).
Beta 2 has its primary receptors in the gastro tract, urinary bladder, bronchial tree and in the skeletal muscle arteries. They dilate the vessels so that they can receive increased blood flow when epinephrine is present. They also stimulate the smooth muscles of the bronchioles of the lungs, allowing more air flow. In the gastrointestinal tract, they can be found in the small intestine stomach, colon and rectum. They effect muscle tone to enable greater filling. (Upchurch,