Equine Thyrotoxicosis Quiz

A condition where the thyroid gland produces too much thyroid hormone.

A group of drugs that block the production of thyroid hormones.

A key enzyme involved in thyroid hormone synthesis.

Drugs like methimazole and propylthiouracil that directly inhibit thyroid peroxidase, thus reducing thyroid hormone production.

Plants from the Brassica genus, such as cabbage and kale, contain compounds that can inhibit thyroid peroxidase, thus exhibiting antithyroid activity.

Iodide (I-) is converted to iodine (I2) by the enzyme thyroid peroxidase (TPO).

Iodine (I2) is incorporated into tyrosine residues of thyroglobulin, forming monoiodotyrosine (MIT) and diiodotyrosine (DIT).

Two molecules of DIT combine to form T4, while MIT and DIT combine to form T3.

Thyroid releasing hormone (TRH) is secreted by the hypothalamus when T3 and T4 blood levels are low.

Thyroid stimulating hormone (TSH) is released by the pituitary gland after being stimulated by TRH.

TSH stimulates thyroid hormone synthesis within the thyroid follicle, among other functions.

High levels of T3 and T4 inhibit both TRH and TSH secretion, forming a negative feedback loop.

Thyroid hormones are stored in the colloid of the thyroid follicle until they are stimulated for secretion.

TSH stimulation triggers the endocytosis of iodinated thyroglobulin from the colloid.

Thyroglobulin is hydrolysed in lysosomes after endocytosis.

T3 and T4 are released from the thyroid gland following deiodination (removal of iodine) and are secreted into the circulation.

In the bloodstream, thyroid hormones travel bound to thyroxine-binding protein (TBP).

T4, the main secretory product, is less potent than T3 and is converted to T3 in target tissues by 5'-deiodinase.

T3 binds to the thyroid hormone receptor (THR) in the nucleus, forming a transcription factor complex.

The transcription factor complex binds to thyroid response elements (TRE), ultimately leading to the production of proteins involved in metabolism.

A medication used to treat hyperthyroidism in cats, it inhibits thyroid peroxidase and is available in oral and transdermal forms. It is often given twice or three times a day initially, but can be reduced to once a day as the condition improves.

A common drug used to treat hyperthyroidism, but its use has been decreasing due to serious side effects like autoimmune reactions and blood disorders.

A slower-acting antithyroid drug that is a derivative of methimazole. It is broken down in the body to its active form, methimazole.

A type of hyperthyroidism in cats that can be treated with methimazole. It is characterized by excessive thyroid hormone production.

The main active form of carbimazole, which inhibits thyroid peroxidase and reduces thyroid hormone production.

One of the serious side effects of antithyroid drugs, particularly with prolonged use. It involves the destruction of red blood cells.

A condition characterized by excessive thirst, often associated with diabetes.

The production of a large volume of urine, commonly seen in diabetes due to the body's inability to effectively reabsorb glucose.

A group of metabolic disorders characterized by high blood glucose levels due to defects in insulin secretion and/or action. Type 1 diabetes results from autoimmune destruction of pancreatic beta cells, while Type 2 diabetes is characterized by insulin resistance.

The hormone produced by the beta cells of the pancreas that plays a crucial role in regulating blood sugar levels. Insulin facilitates the uptake of glucose into cells, promoting its use for energy or storage.

A precursor form of insulin that is cleaved into active insulin within the pancreas. Proinsulin consists of A and B chains linked by a connecting peptide.

The release of insulin from beta cells in the pancreas occurs through this process, in which the insulin-containing vesicles fuse with the cell membrane, releasing the hormone into the bloodstream.

The process by which glucose triggers insulin release from beta cells. Increased ATP levels close potassium channels, leading to cell depolarization and calcium influx, which ultimately initiates insulin secretion.

A condition that disrupts the normal function of islet cells in the pancreas, leading to impaired insulin secretion, ultimately resulting in diabetes. This can occur due to autoimmune destruction of beta cells (Type 1 diabetes) or insulin resistance (Type 2 diabetes).

A condition where the adrenal glands produce too much cortisol, leading to various symptoms such as weight gain, muscle weakness, and increased thirst.

A type of drug that inhibits the production of glucocorticoids (like cortisol) by the adrenal glands, often used to treat hyperadrenocorticism.

A drug used to treat hyperadrenocorticism in dogs, cats, and horses. It works by suppressing the adrenal cortex, which is responsible for cortisol production.

A drug used to treat hyperadrenocorticism in dogs. It acts by destroying the cells in the adrenal glands that produce cortisol, effectively reducing cortisol levels.

A drug used to treat hyperadrenocorticism, but with lower efficacy than trilostane and mitotane. It works by inhibiting the production of cortisol.

A drug that may be used to treat hyperadrenocorticism, but less and with less efficacy.

The outer layer of the adrenal gland, responsible for producing various hormones, including cortisol.

The main hormone produced by the adrenal cortex, responsible for regulating blood sugar, blood pressure, and stress responses.

Insulin cannot be taken orally (by mouth) because it is a protein and would be broken down in the digestive system.

Insulin is available in different forms based on how quickly they start working and how long they last (duration of action).

Fast-acting insulin (lispro, aspart, regular) has a quick onset and short duration, used for complicated diabetes and diabetic ketoacidosis.

Intermediate-acting insulin (NPH, Lente) has a moderate onset and duration, used for uncomplicated diabetes.

Long-acting insulin (glargine, detemir, protamine zinc) has a slower onset and longer duration, used for uncomplicated diabetes.

The strength of insulin refers to its ability to lower blood glucose levels.

Insulin is available in solutions (for injections) and suspensions (for subcutaneous injection).

Insulin is measured in International Units (IU), with 1 IU being the equivalent of 34.7µg of pure crystalline insulin.

Specialized syringes are used for administering insulin, calibrated in IU instead of volume.

Insulin injections are often given subcutaneously (SC) for intermediate and long-acting insulins, while short-acting is given via IV, IM, and SC.

Hypoglycemia (low blood sugar) is a common adverse effect of insulin treatment, and can be treated with glucose or dextrose.

Sulfonylureas (e.g., glipizide) are oral hypoglycemic agents that stimulate the pancreas to secrete more insulin.

Metformin is an oral antihyperglycemic agent that reduces hepatic glucose production and improves insulin sensitivity. It is primarily used for humans with Type 2 diabetes.

Acarbose is an alpha glucosidase inhibitor that delays and reduces postprandial (after meal) hyperglycemia.

Glucagon-like peptide 1 (GLP-1) is a hormone that enhances insulin secretion, suppresses glucagon release, and slows gastric emptying.

Velagliflozin (Senvelgo) is an oral hypoglycemic agent that inhibits the sodium-glucose co-transporter 2 (SGLT-2) in the kidney, increasing glucose excretion in urine, and thus lowering blood glucose.