17310 juxtacellular neuronal labelling microelectrodes  (Microelectrodes Inc)

Journal: Neuromethods

Article Title: Stimulation and Inhibition of Neurons

doi: 10.1007/978-1-62703-233-9

Figure Lengend Snippet: Fig. 2. A pulse generator circuit for juxtacellular neuronal labelling. The device is based on a PIC microcontroller (PICAXE 08M; available from a range of electronic component suppliers or online, e.g. at http://www.techsupplies.co.uk ) and has been designed so that the intensity of the current pulses is easy to set. The circuit is powered by a 9 V DC plug pack. The PICAXE chip is programmed using BASIC code that raises the voltage on pins 6 and 7 of the microcontroller chip to 5 V for 200 ms. At the end of the 200 ms pulse, the voltage drops to 0 V for another 200 ms, which is equivalent to a pulse train of 2.5 Hz with a 50% duty cycle. The pulse at pin 6 controls a light-emitting diode (LED) which signals operation of the pulse generator, while the pulse at pin 7 is connected to a voltage divider circuit.

Article Snippet: 17310 Juxtacellular Neuronal Labelling Microelectrodes are pulled from borosilicate glass capillaries (1.5– 2.0 mm OD) and are fi lled with a solution containing 1.5–5% biotinamide ( N -2-aminoethyl biotinamide hydrobromide, Invitrogen, Eugene, OR, USA; see Sect.

Techniques:

Journal: Neuromethods

Article Title: Stimulation and Inhibition of Neurons

doi: 10.1007/978-1-62703-233-9

Figure Lengend Snippet: Fig. 4. Equipment required for juxtacellular neuronal labelling. An intracellular electrometer ampli fi er ( a ) capable of delivering current pulses is an essential element. The intracellular ampli fi er is coupled to a bandpass ampli fi er ( b ) whose output is monitored using an oscilloscope ( c ), a computerised data acquisition system ( d ) and an audio monitor ( e ). Positive current pulses are applied juxtacellularly via the ampli fi er probe connected to the recording microelectrode. Pulses are generated by the pulse generator ( f ). The pulse generator can be a conventional laboratory stimulator or a dedicated pulse generator as described in this chapter. During application of the juxtacellular current, the sweep of the oscilloscope should be syn- chronised with the pulses so that entrainment of the recorded neuron can be constantly monitored. The sweep can be synchronised by connecting the ‘monitor’ output of the pulse generator to the external input of the oscilloscope time base. The time base should be set to 100 ms/division. It is also prudent to monitor the pulsed output of the electrometer to detect changes in electrode impedance that may result from blockage of the electrode.

Article Snippet: 17310 Juxtacellular Neuronal Labelling Microelectrodes are pulled from borosilicate glass capillaries (1.5– 2.0 mm OD) and are fi lled with a solution containing 1.5–5% biotinamide ( N -2-aminoethyl biotinamide hydrobromide, Invitrogen, Eugene, OR, USA; see Sect.

Techniques: Generated