AUTONOMIC DRUGS Flashcards
What are the two anatomical divisions of the nervous system?
Central nervous system (CNS) and peripheral nervous system (PNS)
CNS includes the brain and spinal cord; PNS includes neuronal tissues outside the CNS.
Functionally, how can the nervous system be subdivided?
Autonomic nervous system (ANS) and somatic nervous system
These subdivisions have distinct functions and controls.
What is the primary concern of the autonomic nervous system?
Control and integration of visceral functions necessary for life
Includes functions such as cardiac output, blood flow distribution, and digestion.
True or False: The activities of the autonomic nervous system are under direct conscious control.
False
The ANS operates largely autonomously.
What major influences does the vagus nerve have besides autonomic functions?
Influences immune function and some CNS functions such as seizure discharge
Evidence suggests connections between the ANS and overall health.
What role do autonomic nerves have in relation to cancer?
They can influence cancer development and progression
Emerging evidence points to this connection.
What is the main focus of the motor portion of the somatic nervous system?
Consciously controlled functions
Includes movement, respiration, and posture.
How do the autonomic and somatic systems receive information?
Through afferent (sensory) inputs
They provide information about the internal and external environments.
What common properties do the nervous and endocrine systems share?
High-level integration in the brain, influence on distant body regions, and extensive use of negative feedback
Both systems utilize chemicals for information transmission.
How does chemical transmission occur in the nervous system?
Through the release of transmitter substances into the synaptic cleft
The transmitter binds to receptors on the postsynaptic cell.
What can occur during retrograde transmission?
Modification of the presynaptic neuron’s subsequent activity
This is a less common form of communication in the nervous system.
How can drugs modify autonomic functions?
By mimicking or blocking the actions of chemical transmitters
This selective modification affects various effector tissues.
List examples of effector tissues involved in autonomic functions.
- Cardiac muscle
- Smooth muscle
- Vascular endothelium
- Exocrine glands
- Presynaptic nerve terminals
These tissues respond to autonomic nervous system signals.
What is a downside of many drugs used for other purposes?
They can have unwanted effects on autonomic function
This includes drugs used for allergies and mental illness.
