Male Sexual Response (Nursing)

00:01 So now let's discuss the male sexual response.

00:06 We start with the first E of two.

00:09 That's erection.

00:11 An erection is an enlargement, and stiffening of the penis.

00:16 In an erection, the arterioles are normally constricted.

00:21 But during sexual excitement, the central nervous system activates parasympathetic neurons, which released the chemical nitric oxide.

00:31 Nitric oxide is a neurotransmitter that causes the relaxation of local vascular smooth muscles.

00:40 When the smooth muscles are relaxed, the arterioles begin to dilate or open up.

00:47 The corpus cavernosa of the penis then expands and retards venous drainage leading to an engorgement of the erectile tissue with blood and an enlargement and stiffening of the penis.

01:02 This is initiated by sexual stimuli such as touch, mechanical stimulation, erotic sights, sounds, or smells.

01:13 And erection can be induced or inhibited by emotions or higher mental activity.

01:21 And longitudinal and circular collagen fibers around the penis can prevent the kinking and buckling of the erect penis.

01:31 Also, the corpus spongiosum keeps the urethra open.

01:37 The second E in the male sexual response is ejaculation.

01:42 Ejaculation is the propulsion of semen from the male duct system.

01:49 This is caused by a sympathetic spinal reflex.

01:53 During this process, the bladder sphincter muscles will constrict.

01:58 This will prevent the explosion of urine at the same time that ejaculation occurs.

02:05 Also the ducts and accessory glands are going to contract in order to empty their contents.

02:13 The bulbospongiosus muscles are going to undergo a rapid series of contractions that cause the expulsion of semen at about 500 centimeters per second or 11 miles per hour.

02:28 At this point when the contractions occur, this causes ejaculation.