Nurses union secretary general Seth Panyako and two other officials were on Tuesday released on Sh50,000 personal bond each.
This followed his arrest, alongside two others, 'for inciting Kenyatta National Hospital to strike on Monday'.
He denied the charge of breaching peace and causing disturbance at the referral facility.
Evans Wanyoike and Evans Mwaluko, who were charged alongside Panyako, also denied the charges.
The three appeared before Chief Magistrate Francis Andayi. They also denied taking part in an unlawful assembly.
The officials were rounded up and arrested as they planned to address nurses at the hospital ahead of the protest.
The nurses want the hospital management to allow them to join the Kenya National Union of Nurses.
Several protesting nurses were also arrested and briefly held in custody at the KNH police post.
The health workers further raised security concerns citing an assault on a nurse by a bereaved mother on October 14.