Question

Hormone regulation

6

Test 1.

Decrease glucose tolerance in diabetes mellitus patients is ascertainedwith sugar load. For this glucose level is determined on an empty stomach, then patient drinks glucose solution (accounting 1 gr per 1 kg of body mass). Glucose concentration is measured each 30 minutes during 3 hours. Present graphs in normal state and in glucose intolarance. Explain these curves.

Test 2.

Patient was admitted to hospital with weakness and diarrhea. It was diagnosed choleras. Explain:

a) Present the scheme of liquid volume restoration in organism;

b) Describe all stages of this system functioning;

c) Name hormones maintaining water-salt balance in organism;

d) Describe mechanism and effects of these hormones.

Answer 1

6. Test 1

A glucose tolerance test is used to determine a person's ability to handle a glucose load. The test can show whether a person can metabolize a standardized measured amount of glucose. The results can be classified as normal, impaired, or abnormal. A glucose tolerance test may be used to diagnose type 1 diabetes mellitus, type 2 diabetes mellitus, and gestational diabetes mellitus. It is a blood test that involves taking multiple blood samples over time, usually 2 hours.

Results, Reporting, Critical Findings

Normal Results for Type 1 Diabetes or Type 2 Diabetes

• Fasting glucose level 60 to 100 mg/dL

• One-hour glucose level less than 200 mg/dL

• Two-hour glucose level less than 140 mg/dL

Impaired Results for Type 1 Diabetes or Type 2 Diabetes

• Fasting glucose level: 100 to 125 mg/dL

• Two-hour glucose level 140 to 200 mg/dL

Abnormal (Diagnostic) Results for Type 1 Diabetes or Type 2 Diabetes

• Fasting glucose level greater than 126 mg/dL

• Two-hour glucose level greater than 200 mg/dL

Normal Results for Gestational Diabetes

• Fasting glucose level less than 90 mg/dL

• One-hour glucose level less than 130 to 140 mg/dL

• Two-hour glucose level less than 120 mg/dL

Abnormal Results for Gestational Diabetes

• Fasting glucose level greater than 95 mg/dL

• One-hour glucose level greater than 140 mg/dL

• Two-hour glucose level greater than 120 mg/dL

TEST 2

a) Oral rehydration therapy (ORT) is a type of fluid replacement used to prevent and treat dehydration, especially due to diarrhea.It involves drinking water with modest amounts of sugar and salts, specifically sodium and potassium. Oral rehydration therapy can also be given by a nasogastric tube. Therapy should routinely include the use of zinc supplements.Use of oral rehydration therapy has been estimated to decrease the risk of death from diarrhea by up to 93%.

Oral Rehydration Guidance: No to Some Dehydration

• Give oral rehydration solution (ORS) immediately to dehydrated patients who can sit up and drink. If ORS is not available, you should provide water, broth, and/or other fluids. You should not provide drinks with a high sugar content, such as juice, soft drinks, or sports drinks, because they could worsen diarrhea.
• Offer ORS frequently, measure the amount drunk, and measure the fluid lost as diarrhea and vomitus.
• Give small, frequent sips of ORS to patients who vomit, or give ORS by nasogastric tube.
  • Make ORS with safe water, which is water that has been boiled or treated with household bleach or a chlorine product using the dose recommended in the product’s instructions, at least 15 minutes before adding prepackaged oral rehydration salts. To make the solution, mix the oral rehydration salts (a prepackaged sachet of glucose and electrolytes) with 1 liter of safe water.
• A rough estimate of oral rehydration rate for older children and adults is 100 ml of ORS every 5 minutes, until the patient stabilizes.
• The approximate amount of ORS (in milliliters) needed over 4 hours can also be calculated by multiplying the patient’s weight in kg by 75.
• If the patient requests more than the prescribed ORS solution, give more.
• Patients should continue to eat a normal diet or resume a normal diet once vomiting stops.
• For infants: encourage the mother to continue breastfeeding.

Assessment

• Reassess the patient after 1 hour of therapy and then every 1 to 2 hours until rehydration is complete.
• During the initial stages of therapy, while still dehydrated, adults can consume as much as 1,000 ml of ORS per hour, if necessary, and children as much as 20 ml/kg body weight per hour.
• The volumes and time shown are guidelines based on usual needs. If necessary, you can increase the amount and frequency, or you can give the ORS solution at the same rate for a longer period to achieve adequate rehydration. Similarly, you can decrease the amount of fluid if the patient becomes hydrated earlier than expected.

Intravenous Rehydration Guidance: Severe Dehydration or Shock

• Patients should receive intravenous (IV) rehydration if they have
  • severe dehydration,
  • stupor,
  • coma,
  • uncontrollable vomiting, or
  • extreme fatigue that prevents drinking.
• For severe dehydration, start IV fluids immediately. If the patient can drink, give ORS by mouth while the IV drip is set up. Ringer’s lactate IV fluid is preferred. If not available, use normal saline or dextrose solution.
• It is important to measure the amount of IV fluids delivered and measure the fluid lost as diarrhea and vomitus.

Assessment

• Reassess the patient every 15–30 minutes and continue hydrating. The volumes and time intervals shown are guidelines provided on the basis of usual needs.
  • If necessary, you can increase the rate of fluid administration, or you can give the fluid at the same rate for a longer period, to achieve adequate rehydration. If hydration is not improving, give fluids more rapidly; the patient may need 200 ml/kg or more of intravenous fluids during the first 24 hours of treatment.
  • You can decrease the amount of fluid if the patient becomes hydrated earlier than expected.
  • Give more than the prescribed ORS solution if the patient requests more.
• Switch from intravenous hydration to oral rehydration solution once hydration is improved and the patient can drink. This will conserve IV fluids and reduce the risk of phlebitis and other complications.
  • You can use nasogastric tubes to administer oral rehydration solution if the patient is alert but unable to drink sufficient quantities independently.

Fluid Replacement or Treatment Recommendations

Dehydration Type Treatment Recommendation Administration Method Severe dehydration Intravenous Ringer’s lactate or, if not available, normal saline and ORS as outlined in the guidance above. Do not give plain glucose or dextrose solution. Administer as follows: Age <1 year Timeframe Total volume 0–60 min 30 ml/kg* 60 min–6 h 70 ml/kg 6 h–24 h 100 ml/kg Administer as follows: Age ≥1 year Timeframe Total volume 0–30 min 30 ml/kg* 30 min–3 h 70 ml/kg Some dehydration Oral rehydration solution Administer in first 4 hours: Age All ages Volume of ORS 75 ml/kg in first 4 hours. Then reassess, and if patient still shows signs of dehydration, repeat. If not, use ORS to replace ongoing diarrheal losses using the treatment plan for no dehydration below. Patients do not need IV fluids, but need close monitoring during the first 4 hours No dehydration Oral rehydration solution Administer after each loose stool: Age Volume of ORS <2 years 50–100 ml 2–9 years 100–200 ml ≥10 years As much as patient wants

b) There are 3 stages, the first, stage of inflam- mation, the second, stage of villus fusing and the third, stage of villus resolution.

c) Mineralocorticoids function to regulate ion and water balance of the body. The hormone aldosterone stimulates the reabsorption of water and sodium ions in the kidney, which results in increased blood pressure and volume.Changing salt intake affected levels of both aldosterone and glucocorticoids, the hormones found to rhythmically control the body's salt and water balance. These, in turn, had a number of interesting effects in the body.The body's homeostatic control mechanisms ensure that a balance between fluid gain and fluid loss is maintained. The hormones ADH (antidiuretic hormone, also known as vasopressin ) and aldosterone play a major role in this.

When the body is low in water, the pituitary gland secretes vasopressin (also called antidiuretic hormone) into the bloodstream. Vasopressin stimulates the kidneys to conserve water and excrete less urine.

The body's homeostatic control mechanisms ensure that a balance between fluid gain and fluid loss is maintained. The hormones ADH (antidiuretic hormone, also known as vasopressin ) and aldosterone play a major role in this..

d) Antidiuretic hormone (ADH) is a chemical produced in the brain that causes the kidneys to release less water, decreasing the amount of urine produced. A high ADH level causes the body to produce less urine. A low level results in greater urine production.It's a hormone made by the hypothalamus in the brain and stored in the posterior pituitary gland. It tells your kidneys how much water to conserve. ADH constantly regulates and balances the amount of water in your blood. Higher water concentration increases the volume and pressure of your blood.

Vasopressin, also called antidiuretic hormone, hormone that plays a key role in maintaining osmolality (the concentration of dissolved particles, such as salts and glucose, in the serum) and therefore in maintaining the volume of water in the extracellular fluid . Oxytocin modulates contraction of uterine smooth muscle at parturition, ejection of milk from lactating breasts, and sperm transport and ejaculation in men, whereas vasopressin regulates water permeability of the collecting ducts to alter urine-concentrating ability.

Protein hormones (or polypeptide hormones) are made of chains of amino acids. An example is ADH (antidiuretic hormone) which decreases blood pressure.  Steroid hormones are derived from lipids. Reproductive hormones like testosterone and estrogen are steroid hormones.Antidiuretic hormone stimulates water reabsorbtion by stimulating insertion of "water channels" or aquaporins into the membranes of kidney tubules. These channels transport solute-free water through tubular cells and back into blood, leading to a decrease in plasma osmolarity and an increase osmolarity of urine.More ADH will be released, which results in water being reabsorbed and small volume of concentrated urine will be produced. If a person has consumed a large volume of water and has not lost much water by sweating, then too much water might be detected in the blood plasma by the hypothalamus.