Overview of endocrinology Flashcards
What are the major endocrine glands?
Hypothalamus Pituitary gland Thyroid Adrenal gland Gonads Pancreas Parathyroid glands
What does the hypothalamus secrete?
Releasing & inhibiting hormones
What does the pituitary gland secrete?
Anterior lobe - trophic hormones
Posterior lobe – oxytocin & vasopressin (ADH)
What does the thyroid gland secrete?
Thyroxine, tri-iodothyronine
What do the gonads secrete?
Oestrogens, androgens, progestagens
What does the pancreas secrete?
Insulin, glucagon
What does the parathyroid gland secrete?
Parathyroid hormone
Explain the endocrine signalling mechanism
Hormones released by an endocrine cell into the general circulation and acting on distant target sites
Explain the paracrine signalling mechanism
Hormones released by an endocrine cell which act locally on adjacent cells
Explain the autocrine signalling mechanism
Hormones released by a cell which act back on the same cell
Explain the intracrine signalling mechanism
Conversion of an inactive hormone to an active hormone that acts within that cell
What are the general functions of the endocrine system?
Reproduction, growth and development
e.g. Sex Steroids, thyroid hormones, prolactin, growth hormone
Maintenance of an internal environment
e.g. Aldosterone, parathyroid hormone, vitamin D
Energy production, utilization and storage
e.g. Insulin, glucagon, thyroid hormones, cortisol, growth hormone
What are the chemical classifications of hormones?
Protein/peptide hormones
Steroid hormones (cholesterol)
Amino acid derivatives (tyrosine/tryptophan)
Fatty acid derivatives
Uses of cortisol
Gluconeogenesis
Protein mobilisation
Fat mobilisation
Anti-inflammatory effects
What is a lack of cortisol called?
Addison’s disease
