Neurophysiology of Muscle Contraction

Here are the study notes for the text:

Hyperpolarization

• Hyperpolarization is a state where the resting potential of a neuron becomes more negative than usual.

Channels and Neurotransmitters

• There are several types of channels in neurons, including:
  • Sodium channels (Na+)
  • Potassium channels (K+)
  • Calcium channels (Ca2+)
  • Chloride channels (Cl-)
• Neurotransmitters are chemical messengers that transmit signals between neurons, including:
  • Acetylcholine
  • Substance P
  • Endorphins
  • Somatostatin

Resting Potential

• The resting potential of a neuron is the electrical potential of the neuron when it is not actively transmitting a signal.
• The resting potential is determined by the concentration gradient of ions across the neuron membrane.
• The resting potential is typically around -70mV.

Action Potential

• An action potential is a rapid change in the electrical potential of a neuron that allows it to transmit a signal.
• The action potential is generated by the depolarization of the neuron membrane, which allows sodium ions to rush in and potassium ions to rush out.
• The action potential is propagated along the length of the neuron by the opening and closing of voltage-gated ion channels.

Neurophysiology

• Neurophysiology is the study of the functions and processes of the nervous system.
• Neurophysiology includes the study of:
  • Neural signaling and transmission
  • Synaptic plasticity and learning
  • Neural circuits and systems
  • The neural basis of behavior and cognition

Hormones and Regulation

• Hormones are chemical messengers that regulate various physiological processes in the body.
• Hormones can be classified into:
  • Steroid hormones (e.g. testosterone, estrogen)
  • Peptide hormones (e.g. insulin, growth hormone)
  • Amine hormones (e.g. epinephrine, norepinephrine)
• Hormonal regulation involves the feedback mechanisms that control hormone production and secretion.

Thyroid Hormone

• Thyroid hormone is produced by the thyroid gland and regulates metabolism and energy production.
• Thyroid hormone can be classified into:
  • Triiodothyronine (T3)
  • Thyroxine (T4)
• Thyroid hormone plays a crucial role in regulating metabolic rate, growth, and development.

Adrenal Gland

• The adrenal gland is a paired gland located on top of the kidney that produces hormones that regulate various physiological processes.
• The adrenal gland produces:
  • Aldosterone (regulates electrolyte balance and blood pressure)
  • Cortisol (regulates stress response and metabolism)
  • Epinephrine and norepinephrine (regulate sympathetic nervous system activity)

Insulin and Glucagon

• Insulin is a hormone produced by the pancreas that regulates blood sugar levels by promoting glucose uptake in cells.
• Glucagon is a hormone produced by the pancreas that regulates blood sugar levels by promoting glucose release from storage sites.

Progesterone

• Progesterone is a hormone produced by the corpus luteum that regulates the female reproductive cycle and pregnancy.
• Progesterone prepares the uterus for implantation of a fertilized egg and maintains pregnancy.

Anti-Inflammatory Response

• The anti-inflammatory response is a response to tissue damage or infection that involves the activation of immune cells and the release of chemical mediators.
• The anti-inflammatory response involves the activation of:
  • Leukocytes (white blood cells)
  • Cytokines (signaling molecules)
  • Chemokines (signaling molecules)
• The anti-inflammatory response helps to remove pathogens and repair damaged tissue.

Gastrointestinal Hormones

• Gastrointestinal hormones regulate various aspects of digestion and nutrient absorption.
• Examples of gastrointestinal hormones include:
  • Gastrin (regulates stomach acid secretion)
  • Cholecystokinin (regulates gallbladder contraction and pancreatic enzyme secretion)
  • Secretin (regulates pancreatic bicarbonate secretion)
  • Motilin (regulates small intestine motility)