1. Function of the kidneys 1.Excretion of metabolic waste products. 2.Regulation of the volume and composition of the body’s internal environment, extracellular fluid

2. What determines the composition of body fluids? It has been said that the composition of body fluids is determined not by what the mouth takes in, but by what the kidney keeps..Because of the kidney’s perfusion with blood, it results in the formation of urine, which is a fluid of varying composition.

3. What carries blood to the kidney? What carries blood away from the kidney? Renal artery carries blood to the kidney. Renal vein carries blood away from the kidney.

4. Where does the renal artery arise from? Where does the renal vein empty into? The renal artery arises from the aorta. The renal vein empties directly into the caudal vena cava.

5. What does the kidney look like? It varies with the species: It’s generally described as a bean-like structure. In a horse it’s often described as heart shaped In cattle its lobulated.

6. What is the renal hilus and why is it important? It’s that indented area on the concave side of the kidney through which the ureter, blood vessels, and nerves or lymphatics enter or leave. What is the renal pelvis? It’s the expanded origin of the ureter within the kidney. This is where the final discharge of urine from the collecting ducts is received.

7. Once the urine is in the renal pelvis, how does it get to the bladder? The ureter conveys urine from the renal pelvis to the bladder. This is cool. The ureter enters the bladder at an oblique angle (ureterovesicular angle) and thus forms a functional valve to prevent backflow when the bladder is filling. What’s the nerve innervation to the kidney? Sympathetic(ever hear the term scare the piss out of someone?) This is why. Fight, or flight innervation.

8. Difference between smooth and skeletal muscle? The ureter and bladder is smooth muscle which means it’s not under voluntary control where as with the external sphincter it’s a skeletal muscle and you can control its movement. You have to go real bad and your able to hold it. Thank you external sphincter of skeletal muscle.

9. Dogs with urinary incontinence. Some dogs lose control of their bladder. Well they can’t control their sphincter and the have urinary leakage. Sometimes it’s age and sometimes it can be hormonal. Treatment is phenylpropanalomine: “BE CAREFUL” What does it do?? It helps release norepinephrine and epinephrine which are potent for the sympathetic system and shuts the leaking door. There’s a drug called bethanechol chloride which causes contraction of the bladder, why wouldn’t you EVER ….EVER…EVER use it concurrently with phenylpropanalomine?

10. What is the functional unit of the kidney? Nephron. Once you understand the nephron, you understand kidney function. The ascending loop of the loop of Henle and the 1 st half of the distal tubules are referred to as the diluting segment. The late distal tubule allows for reabsorption of water

11. What are the 3 processes involving the nephron? Glomerular filtration Tubular reabsorption Tubular secretion

12. How is the kidney involved in blood pressure? Cells in the nephron(juxtaglomerulare cells) secrete renin which in turn initiates the formation of angiotensin II. Angiotension II will cause constriction of efferent arterioles leading to greater pressure to the kidney(GFR) even though you have low blood pressure. The kidneys will then absorb more water thus increasing bv and then subsequently bp. In addition ang II also promotes the absorption of NA+

13. What is the importance of antidiuretic hormone? ADH. If your dehydrated your posterior pituitary secretes ADH to increase the permeability of the cells for water. If your overhydrated, the rate of ADH is decreased.

14. Is caffeine a diuretic? No more than water. The affect of urinating more is probably due to the stimulant affect of caffeine more than it’s diuretic properties.